Sensor network system and data retrieval method for sensing data

ABSTRACT

This invention enables to easily retrieve real-time information from a large number of sensors connected to a network. A sensor network system includes data collectors that collect data from plural sensors at a specified cycle, a directory server that manages locations and identifiers of data from the sensors, and an event-action controller that, of the data collected from the sensors, monitors preset data to be monitored, and when the data satisfies a preset monitoring condition, executes preset processing.

CLAIM OF PRIORITY

The present application claims priority from Japanese applicationP2005-58769 filed on Mar. 3, 2005, the content of which is herebyincorporated by reference into this application.

BACKGROUND OF THE INVENTION

This invention relates to a technology of using information supplied bya large number of sensors connected with the network.

The Internet and other networks have been used in recent years mainlyfor accessing documents, images, movies, sounds or other stored contentsthrough search engines or previously set links. In other words, thetechnology of accessing the stored contents has been nearly completed.

On the other hand, a technology of transmitting the current informationis streaming technology made up of continuously transmitting imagescaptured by a camera installed at a fixed position (web camera). Latelysensor network technology of acquiring through a network sensing dataacquired from a large number of small wireless sensor nodes isdeveloping (JP 2002-006937 A, JP 2003-319550 A, JP 2004-280411 A, U.S.Patent Application Publication 2004/0093239 Specification, and U.S.Patent Application Publication 2004/0103139 Specification). In recentyears, the expectation is growing high for a sensor network systemenabling to capture real-world information through sensors and usingthis information at a remote place through a network. While the presentservice on the Internet is closed to services on a virtual space, theessential difference of the sensor network from the present Internet isthat it is fused with the real world. The possibility of realizingfusion with the real world enables to provide a variety of servicesdependent on time, location and other situation. The connection of alarge variety of objects present in the real world with a networkenables to realize traceability and to address to the social needs forsecuring “safety” in a wide sense and to the needs of “improvingefficiency” in inventory control and office work.

SUMMARY OF THE INVENTION

However, although the search engine shown in the related art indicatedabove enables to find out the position (address) in the networkconcerned of the data stored in the past, there is a problem in that itis not suited to efficient retrieval of real-time information from ahuge amount of sensor information connected with the network concernedand for the retrieval of changes in information.

Accordingly, this invention aims at realizing a sensor network systemthat can easily acquire real-time information from a lot of sensorsconnected to networks, to monitor desired information in real time froma huge amount of information from the sensors and quickly grasp changesin information.

This invention connects plural distributed servers that store datatransmitted from sensor nodes and a management server that manages thesensor nodes in a network. When executing specified processing based ondata from the sensor nodes, the management server sets a distributedserver of the information storage destination in which the data of thesensor nodes is stored, sets a preset model name for which a managementserver is preset and an information storage destination of the datacorresponding to the model name in a model table, sets a correspondencerelation with semantic information corresponding to the value of thedata in a semantic information managing table, decides the data to bemonitored based on the model name according to a request from the userterminal, and decides a monitoring condition of the data to be monitoredin an event table based on the semantic information. The managementserver notifies the distributed server at the information storagedestination of the data to be monitored and the monitoring conditionthat have been decided. The distributed server receives data transmittedfrom the sensor node based on the notification, monitors the data to bemonitored while comparing with the monitoring condition, and executesprocessing previously set when the monitoring condition is satisfied.

Therefore, by monitoring data in the distributed servers that collectdata, this invention can prevent loads from concentrating on themanagement server that manages a lot of distributed servers, and cansmoothly manage a sensor network system even when the number of sensornodes becomes enormous.

A user who uses a user terminal can monitor desired data from among datapieces of a lot of sensor nodes simply by setting model names andsemantic information. Therefore, the user can obtain only desiredinformation extremely easily and real time out of a lot of sensorinformation.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing the system of the sensor networkrepresenting the first embodiment of this invention.

FIG. 2 is a functional block diagram of the sensor network.

FIG. 3 is a block diagram showing an example of wireless sensor nodeWSN.

FIG. 4 is a graph showing the operating condition of the wireless sensornode and shows the relationship between time and power consumption.

FIG. 5 is an illustration showing an example of the disposition ofwireless sensor nodes.

FIG. 6 is a block diagram showing the relationship between the objectsand the measured data of sensor nodes, and shows the starting time ofmeasurement.

FIG. 7 is a block diagram showing the relationship between the objectsand the measured data of sensor nodes, and shows the state when apredetermined time has passed from the start of the measurement.

FIG. 8 is a graph showing the relationship between the data amount ofthe objects, the amount of measured data of the sensor nodes and time.

FIG. 9 is a block diagram showing the event-action controller of thedistributed data processing server DDS.

FIG. 10 is a detailed description of the event table.

FIG. 11 is a block diagram showing the essential parts of the directoryserver DRS.

FIG. 12 is a detailed description of the sensor information table.

FIG. 13 is a detailed description of the attribute interpretation list.

FIG. 14 is a block diagram showing the relationship between thereal-world model list and the distributed data processing server DDS.

FIG. 15 is a detailed description of the model binding list.

FIG. 16 is a time chart showing the steps of registering the sensorinformation.

FIG. 17 is a data format for registering sensor nodes.

FIG. 18 is a time chart showing the steps of registering the real-worldmodel list.

FIG. 19 is a time chart showing the steps of registering the modelbinding list.

FIG. 20 is a time chart showing an example of responses to the access tothe model binding list.

FIG. 21 is a detailed description of the steps required when theposition of Mr. Suzuki is designated from the model binding list.

FIG. 22 is a detailed description of the steps required when the seatingstate of Mr. Suzuki is designated from the model binding list.

FIG. 23 is a detailed description of the steps required when thetemperature of Mr. Suzuki is designated from model binding list.

FIG. 24 is a detailed description of the steps required when the membersof the meeting room A are designated from the model binding list.

FIG. 25 is a detailed description of the steps required when the numberof persons in the meeting room A is designated from the model bindinglist.

FIG. 26 is a block diagram of the action controller ACC of the directoryserver DRS.

FIG. 27 is a block diagram showing an action executer ACEC constitutingan action controller ACC.

FIG. 28 is an illustration of setting the action table.

FIG. 29 is an illustration of the screen setting the actions displayedin the user terminal UST at the time of registering the action table.

FIG. 30 is also an illustration of the screen setting actions.

FIG. 31 is a detailed description showing entries in the action tableETB of the distributed data processing server DDS.

FIG. 32 is a detailed description showing entries in the action tableATB of the directory server DRS.

FIG. 33 is a time chart showing the sequence of setting a single action.

FIG. 34 is a time chart showing the sequence of responding a singleaction.

FIG. 35 is an illustration of the screen for setting actions displayedon the user terminal UST when a single action with plural events is tobe registered.

FIG. 36 is also an illustration of the screen for setting actionsdisplayed on the user terminal UST when a single action with pluralevents is to be registered.

FIG. 37 is a detailed description showing entries in the event table ofthe distributed data processing server DDS-1.

FIG. 38 is a detailed description showing entries in the event table ofthe distributed data processing server DDS-2.

FIG. 39 is a detailed description showing entries in the action table ofthe directory server DRS.

FIG. 40 is a time chart showing the sequence of setting a single actionwith plural events.

FIG. 41 is a time chart showing the sequence of responding a singleaction with plural events.

FIG. 42 is a block diagram showing the event-action controller EAC ofthe distributed data processing server DDS representing the secondembodiment.

FIG. 43 is a second embodiment, which illustrates the screen for settingactions displayed on the user terminal UST when actions are to beregistered.

FIG. 44 is the second embodiment, which illustrates entries in theevent-action table of the distributed data processing server DDS.

FIG. 45 is a time chart showing the sequence of setting event actions.

FIG. 46 shows a second embodiment and is a timing chart showing the flowof action execution in a distributed data processing server DDS.

FIG. 47 shows a third embodiment and is a block diagram showing anevent-action controller of a distributed data processing server DDS.

FIG. 48 shows the third embodiment and is a block diagram of an actionexecuter ACE of an event-action controller.

FIG. 49 shows a third embodiment and is an explanatory diagramillustrating the flow of executing events and actions in a chain fromthe occurrence of one event.

FIG. 50 shows a third embodiment and is an explanatory diagramillustrating an example of an event-action table.

FIG. 51 shows a third embodiment and is an explanatory diagramillustrating the flow of generating secondary data from plural pieces ofmeasured data.

FIG. 52 shows a third embodiment and is an explanatory diagramillustrating an example of an event-action table at the time ofgeneration of secondary data from plural pieces of measured data.

FIG. 53 shows a third embodiment and is an explanatory diagramillustrating the flow of generating secondary data from plural pieces ofmeasured data by plural distributed data processing servers.

FIG. 54 shows a fourth embodiment and is a block diagram of an actionexecuter ACE of an event-action controller.

FIG. 55 shows a fifth embodiment and is a block diagram showing anevent-action controller of a distributed data processing server DDS.

FIG. 56 shows a fifth embodiment and is an explanatory diagramillustrating an example of an event-action table.

FIG. 57 shows a fifth embodiment and is an explanatory diagramillustrating an example of a script file stored in an exceptionalevent-action table.

FIG. 58 shows a fifth embodiment and is a time chart showing the flow ofsetting of exception event action.

FIG. 59 shows a first variant and is a block diagram showing an actioncontroller ACC of a directory server DRS. and

FIG. 60 shows the first variant and is a block diagram showing an actionexecuter ACEC constituting an action controller ACC.

FIG. 61 is a block diagram showing the system of a sensor networkrepresenting a second variant.

FIG. 62 is also a block diagram showing the system of a sensor networkrepresenting the second variant.

FIG. 63 is a block diagram showing the system of a sensor networkrepresenting a third variant.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

We will describe below an embodiment of this invention with reference todrawings.

FIG. 1 is an illustration of the basic configuration of the sensornetwork system showing the first embodiment of this invention.

<Outline of the System Configuration>

The wireless sensor nodes (WSN) and the wireless mobile sensor nodes(MSN) are nodes installed at predetermined positions, or fixed on apredetermined objects or persons, to gather information on theenvironment or information on the objects to which they are fixed, andto transmit the information to the base stations BST-1 to BST-n. Thesensor nodes are made up of wireless sensor nodes WSN and MSN connectedby wireless communication with the base stations BST-1 to BST-n andwired sensor nodes FSN connected by wired communication with the networkNWK-n. Wireless sensor node WSN, MSN, and wired sensor node FSN aregenerically referred to simply as a sensor node.

The wireless sensor nodes WSN installed at fixed locations, for examplewith their sensor sensing the surrounding situation at regularintervals, transmit the sensing information to the base station BSTpreviously set. The wireless mobile sensor nodes MSN are designed to bemobile being carried by a person or on a car and transmit information tothe nearest base stations BST. Incidentally, when the term representsthe whole (generic term) wireless sensor nodes, it will be representedby the acronym WSN or MSN, and when it represents specific wirelesssensor nodes, it will be represented by the acronym plus extensions suchas WSN-1 to WSN-n or MSN-1 to MSN-n. Other elements will also berepresented likewise without any extension when the whole generic nameis indicated, and when specific elements are indicated, they will berepresented by the acronym plus extensions “−1 to n”.

Each base station BST-1 to BST-n is connected with one or pluralwireless sensor node or nodes WSN or MSN, and each base station BST-1 toBST-n is connected with a distributed data processing server DDS-1 toDDS-n for collecting data transmitted by each sensor node through thenetwork NWK-2 to NWK-n incidentally, the network NWK-2 to NWK-n isdesigned to connect the base stations BST and the distributed dataprocessing servers (distributed servers) DDS. The distributed dataprocessing server DDS may vary the number of connections depending onthe required scale of the system scale.

Each distributed data processing server DDS-1 to DDS-n having a diskdrive DSK for storing the data received from the wireless and wiredsensor nodes (simply referred to hereinafter as “sensor node”), a CPU(not shown) and a memory executes a specified program, collects measureddata transmitted by the sensor nodes as described below, and makesvarious steps such as data storage, data processing, and transmission ofnotices and data to a directory server (managements server) DRS or otherservers through the network NWK-1 according to the conditions previouslyprescribed. Incidentally, the network NWK-1 is made up of a LAN, theInternet and the like.

The data collected from the sensor nodes contains the proper ID foridentifying the sensor nodes and numerical data. The numerical data maycome with a time stamp to indicate when the data is sensed. However, thecollected data as it is not in a form easily understandable for the user(user of the user terminal UST and the like). Therefore, the directoryserver DRS converts the output data of the sensor node into a real-worldmodel that users can understand (person, object, state and the like)based on a definition previously set and present the result to the user.

The data relating to the sensor nodes belonging to the base station BSTin the network NWK-2 to NWK-n to which the distributed data processingservers DDS-1 to DDS-n is connected themselves and the data transmittedby the wireless mobile sensor nodes MSN having moved from other basestations BST is collected and converted as described above. And thewired sensor nodes FSN may be connected with the distributed dataprocessing servers DDS-1˜n.

Obviously the wired sensor nodes FSN may be connected with the basestations BST, and the base stations BST may manage the wired sensornodes FSN in the same way as the wireless sensor nodes.

The network NWK-1 is connected with a directory server. DRS for managingthe real-world models related with the sensing information transmittedfrom the distributed data processing servers DDS, user terminals USTusing the information of this directory server DRS, and an operationterminal ADT for setting and operating the directory server DRS, thedistributed data processing server DDS and the base stations BST, andthe sensor nodes. Incidentally, separate operation terminals may beprovided respectively for the sensor managers who manage the sensornodes and the service managers who manage the service of the sensornetwork.

The directory server DRS provided with a CPU (not shown), a memory and astorage system executes the specified program and manages the objectsrelated with meaningful information as described below.

In other words, when a user requests an access to the real-world modelthrough the user terminal UST, the directory server DRS accesses thedistributed data processing servers DDS-1 to DDS-n having measured datacorresponding to the real-world model, acquires the correspondingmeasured data, converts the sensing data if necessary into a formunderstandable for the users and display the result on the userterminals UST.

FIG. 2 is a functional block diagram of the sensor network shown inFIG. 1. In order to simplify the description, we will show here thestructure of the distributed data processing server DDS-1 only fromamong the distributed data processing servers DDS-1 to DDS-n shown inFIG. 1 and only the structure of the base station BST-1 from among thebase stations BST-1 to BST-n connected with the distributed dataprocessing servers DDS-1. Other distributed data processing servers DDSand other base stations BST are similarly structured.

We will now describe various units in details below.

<Base Station BST>

The base station BST-1 for collecting data from the wireless sensornodes WSN, MSN and wired sensor nodes FSN (hereinafter referred to as“sensor nodes”) includes a command controller CMC-B, a sensor nodemanager SNM, and an event monitor EVM. Incidentally, the sensor nodestransmit measured data by attaching the previously set data ID thereto.

The command controller CMC-B exchanges commands with the commandcontroller CMC-D of the distributed data processing server DDS-1 asdescribed below. For example, in response to a command issued by thedistributed data processing server DDS-1, the command controller CMC-Bsets the parameters of the base station BST-1 and transmits the state ofthe base station BST-1 to the distributed data processing server DDS-1.Or it sets the parameters of the sensor nodes managed by the basestation BST-1 and transmits the state of the sensor nodes to thedistributed data processing server DDS-1.

The sensor node manager SNM maintains the management information(operating condition, residual power and the like) of the sensor nodesunder its management. And when an inquiry has been received from thedistributed data processing server DDS-1 on sensor nodes, the sensornode manager SNM provides the management information instead of and foreach sensor node. The sensor nodes can reduce their own processing loadby assigning the processing load related to management to the basestation BST and can limit any unnecessary power consumption.

When the event monitor EVM has detected any anomaly, the sensor nodemanager SNM updates the management information of sensor nodes andinforms the distributed data processing server DDS-1 of any anomaly thatoccurred in any of the sensor nodes. An anomaly in sensor node includesthe case of no response from the sensor nodes, the case where the powersupply to the sensor nodes has fallen below the previously set value andother situations in which the sensor node function is interrupted orcomes to a halt.

Upon receipt of a command (setting of output timing) from the commandcontroller CMC-D to the sensor nodes, the sensor node manager SNMtransmits this command to the sensor nodes to set the output timing, andupon receipt of a notice showing the completion of setting from thesensor nodes, the sensor node manager SNM updates the managementinformation of sensor nodes. Incidentally, the output timing of sensornodes indicates, for example, the interval between cyclicaltransmissions of data from the wireless sensor nodes WSN to the basestation BST-1.

The base station BST manages the previously set wireless sensor nodesWSN, MSN and wired sensor nodes FSN under its control, and transmits thedata measured by each sensor node to the distributed data processingserver DDS.

<Distributed Data Processing Server DDS>

The distributed data processing server DDS-1 includes a disk drive DSKused for a database DB, a command controller CMC-D described below, anevent action controller EAC, and a database controller DBC.

The command controller CMC-D communicates with the base station BST andthe directory server DRS described below to transmit and receivecommands and the like.

Upon receipt of measured data from the sensor nodes through the basestation BST, the event action controller EAC acquires ID correspondingto the measured data or data ID, reads the rule of event correspondingto the data ID from the table described below (event table ETB in FIG.10) and judges whether an event corresponding to the value of themeasured data has occurred or not. And the event action controller EACtakes an action corresponding to the occurrence of an eventcorresponding to the data ID. When the sensor node has only one sensor,the sensor node ID for identifying the sensor node can be used for thedata ID.

In this embodiment, an event refers to a condition set previously formeasured data (or secondary data). The occurrence of an event means thatmeasured data satisfies a predetermined condition.

And the actions taken include the transformation of measured data (rawdata) into secondary data (processed data) based on the rule set inadvance by the user and the like for each data ID, the storage of themeasured data and secondary data into the database DB through thedatabase controller DBC, or the notification of the same to thedirectory server DRS and the like.

According to the present embodiment, as FIG. 1 shows, the disposition ofplural distributed data processing servers DDS concentrating regionally(or locally) some of them against plural base stations BST enables toprocess separately at different locations information supplied by alarge number of sensor nodes. For example, in offices, a distributeddata processing server DDS may be installed on each floor, and infactories a distributed data processing server DDS may be installed ineach building.

The disk drive DSK of the distributed data processing server DDS-1stores as databases DB the measured data of the sensor nodes WSN, MSN,and FSN that has been received from the base stations BST, secondarydata that has been acquired by processing this measured data, and devicedata relating to the base stations BST.

And the database controller DBC of the data processing server DDS-1stores the measured data outputted by the sensor nodes transmitted bythe event action controller EAC in its database DB. And if necessary itstores the secondary data produced by value processing the measured dataor fusing with other data in its database DB. Incidentally, it updatesdevice data as required from time to time in response to the request ofoperation terminal ADT and the like.

<Directory Server DRS>

The directory server DRS for managing plural distributed data processingservers DDS includes a session controller SES for controllingcommunications from the user terminals UST or operation terminals ADTconnected through the network NWK-1 as stated later on, a model managerMMG, a real-world model table MTB, a system manager NMG, an actioncontroller ACC and a search engine SER.

The model manager MMG manages by using a real-world model list MDLhaving set the correlation between the real-world models (objects)understandable for the user and the measured data or secondary datacollected by the distributed data processing servers DDS from the sensornodes set in the real-world model table MTB. Specifically, thereal-world model table MTB defines semantic information understandableto a user as an object, associates the ID and location (storage place)of measured data (or secondary data) from a sensor node with the object,and converts the measured data from the sensor node into semanticinformation understandable to the user from an attribute interpretationlist ATL described later.

The directory server DRS also manages the position information oflocation (URL and other links) of measured data or secondary datacorresponding to the real world model. In other words, the user canaccess directly the constantly changing measurement information of thesensor nodes by designating the real world model. While the measureddata of the sensor nodes and secondary data increase as the time passes,the real-world model information remains unchanged in its dimension evenafter the passage of the time, and only its contents change. We willdescribe the details of this real-world model later on.

Incidentally, the real-world model table MTB is stored in thepredetermined storage system (not shown in any figure) of the directoryserver DRS.

The action controller ACC of the directory server DRS communicates withthe event action controller EAC and the command controller CMC-D of thedistributed data processing servers DDS, and receives the event actionsetting requests outputted by the user terminals UST and the operationterminals ADT. Then it analyzes the details of the event or action ithad received, and sets the distribution of functions between thedirectory server DRS and the distributed data processing servers DDS-1to DDS-n corresponding to the analysis results. Incidentally, an actionor an event may sometimes relate not only to a distributed dataprocessing server DDS but also plural distributed data processingservers DDS-1 to DDS-n.

The search engine SER refers the real-world model table MTB based on thesearch requests for the objects received by the session controller SES,and searches the database DB of the distributed data processing serversDDS.

If the search request is a query, the search engine SER relates thedatabase DB to the contents of the query, converts the query to the SQL(structured query language) and carries out the search. Incidentally,the database DB to be searched may sometimes cover plural distributeddata processing servers DDS.

And this query relates to “the acquisition of the latest data(snapshot/stream).” Incidentally, “the acquisition of the latest data(stream)” relates to the action setting of the action controller ACC. Inother words, it is enough to set an action in the event actioncontroller EAC of the pertinent distributed data processing server DDSin such a way that the pertinent data may always be transferred to theuser terminal.

Now, the system manager NMG globally manages the distributed dataprocessing servers DDS connected with the network NWK-1 and constitutingthe sensor network, the base stations BST connected with the distributeddata processing servers DDS and the sensor nodes connected with the basestations BST.

The system manager NMG provides an interface related with theregistration and retrieval of the distributed data processing serversDDS, the base stations BST and the sensor nodes to the operationterminals ADT and the like, and manages the condition of each device andthe condition of the sensor nodes.

The system manger NMG may issue commands to the distributed dataprocessing servers DDS, the base stations BST and the sensor nodes andmanages the resources of the sensor network by these commands. By theway, the sensor nodes receive commands from the system manager NMGthrough the command controller CMC-B of the base station BST and thebase stations BST receive commands from the system manager NMG throughthe command controller CMC-D of the distributed data processing serverDDS.

Incidentally, the commands issued by the system manager NMG through thecommand controller CMC-D include reset, set parameters, delete data,transmit data, set standard-type event-action, and the like.

<An Example of Sensor Node>

An example of sensor node will be shown in FIGS. 3 to 5.

FIG. 3 is a block diagram showing an example of wireless sensor nodeWSN. A wireless sensor node WSN includes a sensor SSR for measuringquantity of state (temperature, pressure, position and the like) andchanges in the quantity of state (low temperature/high temperature, lowpressure/high pressure, and the like) of the object of measurement, acontroller CNT for controlling the sensors SSR, an RF processor WPR forcommunicating with the base stations BST, a power supply unit POW forsupplying power to each block SSR, CNT and WPR, and an antenna ANT fortransmitting and receiving RF signals.

The controller CNT reads the measured data of the sensors SSR at apreviously set cycle, adds a previously set data ID to this measureddata and transmits the same to the RF processor WPR. The measured datamay sometimes include time information on the sensing as a time stamp.The RF processor WPR transmits the data received from the controller CNTto the base stations BST.

The RF processor WPR transmits the commands and the like received fromthe base stations BST to the controller CNT, and the controller CNTanalyzes the commands received and proceeds to the predeterminedprocessing (e.g., change of setting and the like). The controller CNTtransmits the information on the remaining power (or amount of electriccharges made) of the power supply unit POW to the base stations BSTthrough the RF processor WPR. In addition, the controller CNT itselfmonitors the remaining power (or the amount of electric charges) of thepower supply unit POW, and when the remaining power has fallen below thepreviously set value, the controller CNT may warn the base stations BSTthat power supply is about to run out.

In order to conduct extended-time measurements with a limited supply ofpower, as shown in FIG. 4, the RF processor WPR is operatedintermittently to reduce power consumption. During its sleep state SLPas shown in the figure, the controller CNT stops driving the sensors SSRand switches from a sleep state to an operating state at a predeterminedtiming to drive the sensors SSR and transmits the measured data.

FIG. 3 shows the case wherein a wireless sensor node WSN has only onesensor SSR. However, plural sensors SSR may be disposed thereon.Alternatively, a memory having a proper identifier ID may be used in theplace of sensors SSR for a wireless sensor node WSN to be used as a RFIDtag.

In FIGS. 3 and 4, a battery may be used for the power supply unit POW,or solar cell, vibrational energy generation or other similar energygeneration units may be used. The wireless mobile sensor node MSN may bedesigned in the same way as shown in FIGS. 3 and 4.

FIG. 5 is a detailed illustration showing an example of sensor nodesconnected with the distributed data processing server DDS-1 shown inFIGS. 1 and 2 above.

In the present embodiment, an example of installing sensor nodes in theoffice, the meeting room A and the meeting room B is shown.

In the office, a base station BST-0 is installed, and a wireless sensornode WSN-0 having a pressure switch as a sensor SSR is installed on thechair in the office. The wireless sensor node WSN-0 is set tocommunicate with the base station BST-0.

A base station BST-1 is installed in the meeting room A, and thewireless sensor nodes WSN-3 to WSN-10 respectively having a pressureswitch as a sensor SSR are installed on the chairs of the meeting roomA. Furthermore, the meeting room A is provided with a wired sensor nodeFSN-1 having a temperature sensor, and the wired sensor node FSN-1 isconnected with the base station BST-1. Each of the wireless sensor nodesWSN-3 to WSN-10 and the wired sensor node FSN-1 are set in such a waythat they can communicate with the base station BST-1.

Similarly a base station BST-2 is installed in the meeting room B, andthe wireless sensor nodes WSN-11 to WSN-18 respectively having apressure switch as a sensor SSR and the wired sensor node FSN-2 having atemperature sensor are installed on the chairs of the meeting room B.These sensor nodes are connected with the base station BST-2.

The employees using the meeting rooms A and B are required to wear awireless mobile sensor node MSN-1 serving as their identification card.The wireless mobile sensor node MSN-1 is constituted as anidentification card with a temperature sensor SSR-1 for measuring thetemperature of the employee (or the ambient temperature) and a tag TG-1storing the proper identifier of the employee (employee ID). Thewireless mobile sensor node MSN-1 can transmit the employee ID and themeasured temperature data to the base stations BST-0, 1 or 2.

<Outline of the Operation of the Sensor Network>

We will then describe the outline of the operation of the sensor networkshown in FIGS. 1 to 5 with reference to FIGS. 6 to 8.

FIG. 6 is a block diagram showing the relationship between the objectsrepresenting the specific forms of the real-world model and the measureddata of the sensor nodes and shows the beginning of measurement, andFIG. 7 shows the situation prevailing after the passage of apredetermined period of time from the situation shown in FIG. 6.

In FIG. 6, the directory server DRS has formed in advance the followingobjects as the real-world model, and defines the same in the real-worldmodel list MDL of the real-world model table MTB. Here, we assume thatMr. Suzuki is an employee using the office or the meeting rooms A and Bshown in FIG. 5, and that he is wearing a wireless mobile sensor nodeMSN-1 shown in FIG. 5 and FIG. 6.

As the sensor information table STB of FIG. 12 shows, the sensorinformation table is defined in such a way that the measured data (e.g.temperature) and position information of each sensor node MSN may bestored in the distributed data processing server DDS designated as thedata link pointer. Here, the position information of the sensor node MSNmay be acquired as the ID information of the base station BST thatdetects the sensor node MSN.

And the real-world model list MDL of the real-world model table MTBcontains a definition that the object representing the position of Mr.Suzuki (OBJ-1) is an object actually located in the link pointer namedmeasured data 1 (LINK-1), and thus manages the relationship ofcorrespondence between the real-world model and the actual dataposition.

In other words, the object representing the position of Mr. Suzuki(OBJ-1) in the real-world model list MDL is related with the storageposition of the distributed data processing server DDS corresponding tothe measured data 1 (LINK-1). In FIGS. 6 and 7, the position informationgiven by the wired mobile sensor node MSN-1 indicating the position ofMr. Suzuki (defined, e.g., as “connected with which base station BST”)is stored in the disk drive DSK 1 of the distributed data processingserver DDS.

When viewed from the user terminal UST, the value of Mr. Suzuki'sposition (OBJ-1) seems to be stored in the real-world model table MTB ofthe directory server DRS. However, the actual data is stored not in thedirectory server DRS, but in the disk drive DSK 1 previously set of thedistributed data processing server DDS.

The object representing the taking seat of Mr. Suzuki (OBJ-2) will bedefined in the real-world model table MTB in such a way that the seatinginformation acquired by the pressure switch (WSN-0) installed on thechair in the office may be stored in the measured data 2 (LINK-2). Inaddition, the distributed data processing server DDS corresponding tothe measured data 2 and the storage position will be defined. In FIGS. 6and 7, the seating information acquired from the MSN-1 and the wirelesssensor node WSN will be stored in the disk drive DSK 2 of thedistributed data processing server DDS-1.

The object representing Mr. Suzuki's temperature (OBJ-3) will be definedin the real-world model table MTB in such a way that the temperaturemeasured by the temperature sensor SSR-1 of the wireless mobile sensornode MSN-1 will be stored in the measured data 3 (LINK-3). In addition,the distributed data processing server DDS corresponding to the measureddata 3 and the storage position will be defined. In FIGS. 6 and 7, thetemperature data acquired from the MSN-1 will be stored in the diskdrive DSK 3 of the distributed data processing server DDS.

The object representing the members of the meeting room A (OBJ-4) willbe defined in the real-world model table MTB in such a way that the nameof employee acquired from the information of the wireless mobile sensornode MSN connected with the base station BST-1 of the meeting room A maybe stored in the measured data 4 (LINK-4). If no pressure switch (WSN-3to WSN-10) is used, the number of persons in the meeting room A may becalculated from the number of the wireless mobile sensor nodes MSNdetected by the base station BST-1 in the meeting room. Further, thedistributed data processing servers DDS corresponding to the measureddata 4 and the storage position will be defined. In FIGS. 6 and 7, theindividual information acquired from the wired mobile sensor node MSN ofeach employee will be stored in the disk drive DSK 4 of the distributeddata processing server DDS.

The object representing the members of the meeting room A (OBJ-5) willbe defined in the real-world model table MTB in such a way that thenumber of persons acquired from the pressure switches (WSN-3 to WSN-10)in the meeting room A may be stored in the measured data 5 (LINK-5). Andthe distributed data processing server DDS corresponding to the measureddata 5 and the storage position will be defined. In FIGS. 6 and 7, theseating information from the wired sensor nodes WSN-3 to WSN-10 will bestored in the disk drive DSK 5 of the distributed data processing serverDDS.

The object representing the temperature of the meeting room A (OBJ-6)will be defined in the real-world model table MTB in such a way that thetemperature measured by the wired sensor node FSN-1 in the meeting roomA may be stored in the measured data 6 (LINK-6). And the distributeddata processing server DDS corresponding to the measured data 6 and thestorage position will be defined. In FIGS. 6 and 7, the temperature datafrom the FSN-1 will be stored in the disk drive DSK 6 of the distributeddata processing server DDS-1.

In other words, each object OBJ defined in the real-world model tableMTB stores the link pointer (LINK) corresponding to the measured data,and although the object data as seen from the user terminal UST may seemto exist in the directory server DRS, the actual data is stored in thedistributed data processing server DDS.

In the link pointer of the information LINK, the storage position of themeasured data measured by the sensor nodes, the secondary data obtainedby converting the measured data into an understandable form for the userand the other data usable for the user are set. The measured data fromthe sensor nodes is collected by each distributed data processing serverDDS, and if an event/action is set as described later on, the measureddata will be processed and will be stored in the predetermineddistributed data processing server DDS as secondary data.

The data from the sensor nodes will be actually collected and processedby the distributed data processing servers DDS, and the directory serverDRS will manage the real-world model, the link pointer of informationand the definition of the sensor nodes.

In this way, the users of the user terminals UST will not be required tolearn the location of the sensor nodes, they will be able to obtain thedesired data corresponding the measurement (or the secondary data) ofthe sensor node by retrieving the objects OBJ.

And as the directory server DRS will manage the link pointer of eachobject OBJ, and the actual data will be stored and processed in thedistributed data processing servers DDS, even if the number of sensornodes turns out to be huge, it will be possible to prevent thedistributed data processing servers DDS from being overloaded. In otherwords, even when a large number of sensor nodes are employed, it will bepossible to suppress the traffic load on the network NWK-1 connectingthe directory server DRS, distributed data processing servers DDS andthe user terminals UST.

In FIG. 7 showing the state after the lapse of a predetermined period oftime after the state of FIG. 6, the actual measured data transmittedfrom the sensor nodes will be written into the disk drives DSK-1 toDSK-6 of the distributed data processing servers DDS-1, and the amountof data will increase as the time passes.

On the other hands, the amount of information stored in the linkpointers LINK-1 to LINK-6 corresponding to the objects OBJ-1 to OBJ-6set in the model list MDL of the real-world model table MTB of thedirectory server DRS remains unchanged even with the passage of time,and the contents of information indicated by the link pointers LINK-1 toLINK-6 change.

In short, the relationship between the amount of information of theobjects OBJ-1 to OBJ-6 managed by the directory server DRS, the amountof data of the measured data 1 to 6 managed by the distributed dataprocessing servers DDS-1 and time is that, while the amount of data ofthe objects is constant as shown in FIG. 8, the amount of measured dataincreases as the time passes.

For example, when a base station BST is connected with hundreds ofsensor nodes, a distributed data processing server DDS is connected withseveral base stations BST, and a directory server DRS is connected withtens of distributed data processing servers DDS, the total number ofsensor nodes will be several thousands or several tens of thousands.Supposing that each sensor node transmits data every minute, hundreds orthousands of measured data pieces will be sent every second to thedistributed data processing server DDS, the presence of an event will bejudged, and if an event has occurred, a predetermined action, such as anotice, data processing or other action, will be taken. If these actionsare to be carried out by a centralized server, the load of the serveritself or that of the network for connecting with the server will bevery large. In addition, the collected data or the secondary data mustbe provided to the user terminals in response to users. Therefore, theload of the server or that of the network will further increase.

To avoid the load increase, the server function is divided on DRS andDDS. The directory server DRS receives access from the user terminalsUST and manages the information link pointers of the sensor nodes. Thedistributed data processing servers DDS manage plural base stations BST,collect and process the data from the sensor nodes.

The information from the sensor nodes is distributed among and collectedby plural distributed data processing servers DDS, and each distributeddata processing server DDS respectively stores or processes the data. Inthis way, the collection and processing of data from a large number ofsensor nodes is distributed and thus the concentration of load intospecific servers can be avoided.

On the other hand, the directory server DRS manages collectively (in acentralized way) the link pointers LINK of information acquired from themeasured data of the sensor nodes and provides the user terminals USTwith the correspondence relationship between the objects and the linkpointers LINK. Users acquire useful information from the data linkpointers by inquiring the directory server DRS on the target objectseven if they have no information regarding the physical position ofsensor nodes. In other words, the centralized management of informationlink pointers by the directory server DRS enables the user terminals USTto acquire the measured data or secondary data concerning the targetsensor node by accessing the directory server DRS without sensor nodeinformation.

The directory server DRS converts the data acquired from the distributeddata processing servers DDS into information (semantic information)understandable for the users based on the attribute interpretation listATL and provides the result to the user terminals UST.

The objects stored in the directory server DRS are set and modifieddepending on the system structure, and do not change chronologically asthe measured data retrieved by the sensor nodes does. Therefore, thepart that controls collectively the objects is not affected bychronological changes in the load of the measured data. As a result, thedirect exchange of the sensor node data with the distributed dataprocessing servers DDS is restricted, and thus the possibility that theoverload of the network NWK-1 connected with the directory server DRS issuppressed.

FIGS. 6 and 7 show the case where separate distributed data processingservers DDS are respectively connected with a disk drive DSK. However,as shown in FIG. 5, a distributed data processing server DDS may beprovided and plural disk drives DSK may be connected therewith. It isalso possible to connect the disk drives with grouped plural distributeddata processing servers DDS.

<Relationship Between the Measured Data and the Event>

And now the relationship between measured data to be collected by thedistributed data processing server DDS and the event/action based on themeasured data will be shown in FIGS. 9 and 10.

In FIG. 9, the event-action controller EAC of the distributed dataprocessing server DDS has an event table ETB for correlating themeasured data collected by the base stations BST with events.

As FIG. 10 shows, a record of the event table ETB is made up of a dataID allocated to each sensor node and given to the measured data(corresponding to the data ID shown in FIGS. 12 and 14), EVTconstituting the criteria of judging the occurrence of an event relatingto the measured data, and a data holder DHL for determining whether themeasured data should be stored in the database DB or not.

For example, in the figure, the measured data whose data ID is “XXX”notifies the directory server DRS on the occurrence of an event when itsvalue is greater than A1. Incidentally, the measured data whose data IDis “XXX” are set in such a way that they will be written on the diskdrive DSK whenever the data arrives. Storage to the disk DSK is based onsetting information set in an action field of an event table end ETB.

The distributed data processing server DDS receives the measured dataacquired from the base station BST at first by the sensing data IDextractor IDE and extracts the data ID or ID given to the measured data.And the sensing data ID extractor IDE sends the measured data to thelatest data memory LDM.

The extracted data ID will be sent to the event search engine EVS tosearch the event table ETB, and when a record whose data ID matches isfound, the event contents EVT of the record and the measured data willbe sent to the event condition parser EVM.

The event condition parser EVM compares the value of the measured dataand the event contents EVT, and when the conditions are satisfied, theevent condition parser EVM notifies the directory server DRS that anevent has occurred from a network processor NWP through the networkNWK-1. And the event condition parser EVM transmits the request of thedata holder DHL to the latest data memory.

Regarding the data which the data holder DHL of the event table ETB isready to accept, the database controller DBC will receive the data fromthe latest data memory LDM and write the data on the disk drive DSK.

When the network processor NWP has received a reference request for themeasured data from the directory server DRS, the distributed dataprocessing server DDS will transmit the access request to the dataaccess receiver DAR.

If the request for data access is for the latest data, the data accessreceiver DAR reads the measured data corresponding to the data IDcontained in the access request from the latest data memory LDM, andreturns the same to the network processor NWP. Or, if the access requestis for the past data, the data access receiver DAR reads the measureddata corresponding to the data ID contained in the access request fromthe disk drive DSK, and returns the same to the network processor NWP.

Thus, the distributed data processing server DDS retains the latest datain the latest data memory LDM from among the sensor node data collectedfrom the base stations BST, and records other data in the disk drive DSKfor reference in the future. And it is also possible to hold the data inthe disk drive DSK only when an event has occurred to save the disccapacity. By this method, it will be possible to manage plural basestations BST (in other words a large number of sensor nodes) with asingle distributed data processing server DDS.

<Details of the System Manager NMG and the Model Manager MMG>

<System Manager NMG>

FIG. 11 shows the details of the system manager NMG and the modelmanager MMG of the directory server DRS and the real-world model tableMTB shown in FIG. 2.

The system manager NMG of the directory server DRS includes a sensorinformation table STB for managing the sensor nodes, a registrationinterface for registering sensor nodes in the sensor information tableSTB, and a retrieval interface for retrieving the contents of the sensorinformation table STB. Incidentally, here the sensor information tableSTB will be managed by the sensor operation terminal ADT-A.

As FIG. 12 shows, the sensor information table STB is made up of arecord of the data ID allocated in advance for each sensor node, thesensor type indicating the type of sensor node, the meaning indicatingthe object of measurement by the sensor node, the contents ofmeasurement measured by the sensor node, the location indicating theposition (or object) of the sensor node, the observation intervalindicating the frequency by which the sensor node detects themeasurement from the object of measurement, and the data link pointershowing the link pointer of the data measured (the position of storagein the distributed data processing server DDS-1 to DDS-n) which aremanaged by a data ID for identifying the sensor node as an index.

For example, the table shows that the tag TG-1 of the wireless mobilesensor node MSN-1 constituted as an identification card shown in FIG. 5is allocated 01 as a data ID of a sensor node, and the object ofmeasurement is the location (position) of the wireless mobile sensornode MSN-1, the frequency of measurement is every 30 seconds, and themeasurement data is stored in the distributed data processing serverDDS-1.

Similarly, the table shows that the sensor SSR-1 disposed in thewireless mobile sensor node MSN-1 constituted as an identification cardis allocated a data ID of 02, that the object of measurement is theambient temperature, that the frequency of measurement is every 60seconds, and that the measured data is stored in the distributed dataprocessing server DDS-2.

This sensor information table STB contains data set by the sensoroperation terminal ADT-A, and the sensor manager and the service managercan learn the functions and position of the sensor nodes and the linkpointers of the measured data by referring the sensor information tableSTB.

When the frequency of measurement of data by the sensor node is notconstant, like the seating sensor of the node ID=03 shown in FIG. 12,only when the sensor has detected a specific state, this state will benotified to the distributed data processing server DDS irrespective ofthe frequency when the observation interval is set as “event.”

<Model Manager MMG>

We will now describe the model manager MMG and the real-world modeltable MTB shown in FIG. 11.

The real-world model table MTB managed by the model manager MMG includesan attribute interpretation list ATL for interpreting what the measureddata means, a real-world model list MDL showing the relationship ofcorrespondence between the model name of the object OBJ-1 to OBJ-n shownin FIG. 6 and the actual information storage position and a modelbinding list MBL showing the relationship of correlation among theobjects OBJ-1 to OBJ-n.

And the model manager MMG includes an attribute interpretation listmanager ATM for managing the attribute interpretation list ATL, areal-world model list manager MDM for managing the real-world model listMDL, and a model binding list manager MBM for managing the model bindinglist MBL in order to manage each list of this real-world model tableMTB, and each manager includes respectively a registration interface forregistering/changing the list and a retrieval interface for retrievingeach list.

It should be noted here that the real-world model table MTB should bemanaged by the service manager who uses the service operation terminalADT-B. Furthermore, the sensor operation terminal and the serviceoperation terminal shown in FIG. 11 may be integrated into a singleoperation terminal as shown in FIG. 1.

And the user terminal UST for using the sensor network will be used toretrieve objects OBJ from the desired list through the retrievalinterface of each list.

In the first place, the attribute interpretation list ATL managed by theattribute interpretation list manager ATM includes a table forconverting the output value of sensor nodes into meaningful informationas shown in FIG. 13 because the return values (measurements) of thesensor nodes WSN, MSN and FSN and the secondary data converted by thedistributed data processing servers DDS cannot be understood easily asthey are by the users of the user terminals UST (hereinafter referred tosimply as “user”). FIG. 13 is previously set according to the objectsOBJ-1 to OBJ-n.

In FIG. 13, the name table ATL-m is related with the position of Mr.Suzuki OBJ-1 shown in FIG. 6, and as shown in FIG. 12, the personal namecorresponding to the return value (measurement) from the identifier setin the tag TG set in the sensor node MSN-1 whose sensor type isidentification card is indicated in the meaning column.

In FIG. 13, the place table ATL-p is a table showing the position of anemployee wearing an identification card, and the name of placecorresponding to the return value (e.g. the ID of the base stationconnected with the sensor node) is indicated in the meaning column. Forexample, a return value of 01 means that the place is an office.

The seat table ATL-s of FIG. 13 shows the state of persons sitting onthe chairs in the office or in the meeting room A shown in FIG. 5, andstores the state of persons sitting (present or absent) corresponding tothe return value (measurement) of wireless sensor nodes WSN-3 to WSN-10installed on each chair (each wireless sensor node WSN-3 to WSN-10). Forexample, a return value of 00 shows that the person is present (seated),and a return value of 01 shows that the person is absent.

In the same way, the temperature table ATL-t of FIG. 13 is a table ofvalues given by the temperature sensors (SSR-1, FSN-1 and 2 of MSN-1)shown in FIG. 5, and the function f (x) for converting the return value(the measured data of the temperature sensors) into temperature y willbe stored in the meaning column.

In FIG. 13, the number of persons table ATL-n is a table showing thenumber of persons in the meeting room A, and the number of personscorresponding to the return value (the number of persons seated shown bythe chair sensors in the meeting room A, or the number of mobile sensornodes MSN in the meeting room A) will be indicated in the meaningcolumn.

Thus, the attribute interpretation list ATL is a list defining themeaning corresponding to the measured data, and respective table will becreated corresponding to the objects formed.

Then, the real-world model list MDL is a list created in advance by theservice managers and the like, and as shown in FIG. 14 the position ofinformation corresponding to the model name set for each object will bestored in the information link pointer. In other words, the combinationof model name, information link pointer and data ID constitutes areal-world model list MDL.

The directory server DRS manages only meaningful information that theusers can understand from the model list MDL, and this meaningfulinformation will be located in any of the distributed data processingservers DDS-1 to DDS-n. As a result, the objects OBJ defined in themodel list MDL indicate where the substance of the meaningfulinformation is located in the information link pointer. Incidentally,this information link pointer is created in advance by the servicemanager and the like. In the same way, the data ID is a valuecorresponding to the sensor data (data acquired directly from the sensornode or secondary data acquired by processing) serving as the basis ofthe object value.

In FIG. 14, for example an information link pointer named LINK-1 for Mr.Suzuki's position OBJ-1 is stored, and this information link pointerstores URL, path and the like. When this object is retrieved from theuser terminals UST, meaningful information (substance of the object) canbe obtained from the information link pointers.

For example, when key word and the like are transmitted from the userterminals UST to the search engine SER of the directory server DRS, thelist of model names including the key words from among the model namesof the model list MDL will be returned from the search engine SER. Whenthe user operating the user terminal UST has selected the desired modelname, at first the directory server DRS acquires the data correspondingto the information link pointer from the distributed data processingserver DDS created in the information link pointer LINK.

The directory server DRS converts the acquired data into informationthat the user can understand based on the attribute interpretation listATL and transmits the same to the user terminals UST.

Therefore, users can acquire necessary information in the form ofunderstandable information even if they have no knowledge on theindividual sensor nodes nor of their location.

Since it is no longer necessary to convert the data collected from thesensor nodes into a form understandable for the users every time theyare collected, in the distributed data processing server DDS, it ispossible to drastically reduce the load of the distributed dataprocessing servers DDS that collect and/or manage the data of a largenumber of sensor nodes. This conversion processing of data conducted bythe directory server DRS if necessary at the request of users caneliminate any unnecessary conversion operation, and thus it will bepossible to make the sensor network resources to function efficiently.

The model binding list MBL showing the relationship of correlation amongthe objects OBJ-1 to OBJ-n summarizes the related information on theelements common with the objects OBJ of the real-world model list MDL.

As an example of the model binding list MBL, as FIG. 15 shows, “personalname” (“Mr. Suzuki” in the figure) and elements related with “themeeting room A” are extracted as common elements among the objects OBJof the real-world model list MDL. For example, as objects OBJ relatedwith the personal name of “Mr. Suzuki” registered in the meaning columnof the name table ATL-m of the attribute interpretation list ATL shownin FIG. 13, there are position OBJ-1, seated state at the employee's ownseat in the office OBJ-2, and temperature OBJ-3, and the link pointersof the objects related with the personal name of Mr. Suzuki are set in atree structure as “position” LINK-1, “seated state” LINK-2, and“temperature” LINK-3 as shown in the figure, and this will constitute amodel binding list MBL-P related to personal name.

In the same way, when the real-world model list MDL is viewed from theelement of the meeting room A, there are objects OBJ-4 to OBJ-6 of“members,” “number of employees” and “temperature.” The information linkpointers LINK-4 to LINK-6 of the objects related with the place of themeeting room A are set in a tree structure as “members,” “number ofemployees” and “temperature.” Thus, the model binding list MBL-R relatedwith the meeting room A will be constituted.

Thus, the model binding list MBL will constitute a source of informationrelating different pieces of information having common elements out ofthe elements of the objects of the real-world model list MDL. It shouldbe noted that different elements of this model binding list MBL wererelated in advance by the service manager and the like.

<Operation of the Model Manager MMG>

We will describe the operation of the sensor network system as follows.

<Registration of the Sensor Nodes>

To begin with, we will describe the procedure of registering sensornodes with reference to FIGS. 16 and 17. The sensor manager installs asensor node at a predetermined place or on an employee and thenregisters the sensor node on the directory server DRS according to thetime chart shown in FIG. 16.

In FIG. 16, the sensor manager accesses the directory server DRS throughthe sensor operation terminal ADT-A, and accesses the registrationinterface of the system manager NMG. Then, the sensor manager sets thedata ID, the sensor type, attribute, measurement values, place ofinstallation, interval of observation, and the data link pointer fromthe sensor operation terminal ADT-A using the data format shown in FIG.17, and transmits the same to the system manager NMG of the directoryserver DRS as a request for registration (RG-1). Here, before proceedingto registration, the data link pointers should be secured and theattribute should be designated to the distributed data processing serverDDS that is supposed to receive the sensor node data.

Upon receipt of this request for registration, the system manager NMG ofthe directory server DRS adds the sensor node information for which therequest for registration was presented to the sensor information tableSTB shown in FIG. 12. And the system manager NMG allocates a data ID tothe newly added sensor node. This data ID may be allocated from thesensor operation terminal ADT-A.

The system manager NMG allocates the link pointer of the measured dataof the sensor node for which a request for registration was presented tothe distributed data processing server DDS designated as a data linkpointer and then completes a record of the sensor information table STB.

Finally, the system manager NMG returns a notice of completion (ACK) tothe sensor operation terminal ADT-A, indicating that a new record wassuccessfully added.

Incidentally, although not shown in any figure, upon receipt of a noticeof registration of a sensor node from the directory server DRS, thedistributed data processing server DDS issues a command to enable thesensor node to send sensing data with a predetermined observationfrequency. The sensor manager SNM of the base station BST will receivethe registration of the data ID and the observation interval.

In this way, the new sensor node will be able to transmit the measureddata to the distributed data processing server DDS to which this sensornode belongs through the base station BST.

<Definition of Objects>

Then, we will describe the operation of creating the relationshipbetween the measured data of the sensor node and the objects concerningthe sensor node registered on the directory server DRS in FIGS. 16 and17 above with reference to FIG. 18. It should also be noted that thisoperation is to be carried out by the service manager of the sensornetwork.

In FIG. 18, the service manager accesses the directory server DRS fromthe service operation terminal ADT-B to access the retrieval interfaceof the system manager NMG. Then, the service manager retrieves thedesired sensor nodes based on the data ID and the like and returns thesensor nodes meeting the retrieval conditions to the service operationterminal ADT-B.

The service operation terminal ADT-B shows the retrieval result of thesensor nodes that have been received from the system manager NMG on thedisplay devices and the like.

The service manager selects a desired sensor node from the sensor nodesdisplayed on the service operation terminal ADT-B, designates theobjects to be correlated with the measured data of this sensor node, andregisters the same on the model manager MMG of the directory server DRS.

For example, the service manager registers the object OBJ-1 of “Mr.Suzuki's position” as the object of the identification card-type sensornode (MSN-1 of FIG. 5) of data ID=01 of the sensor information table STBshown in FIG. 12. This registration results in the creation of areal-world model list (MDL) showing the relations between the object andits information link (FIG. 14).

The model manager MMG issues a predetermined command to the distributeddata processing server DDS-1 to, for example, store the position of thebase station BST having received the mobile sensor node MSN with a tagID TG-1 (Mr. Suzuki's identifier) with regards to the object OBJ-1 of“Mr. Suzuki's position” in the distributed data processing server DDS-1.

The distributed data processing server DDS-1 is set to register anaction in the event-action controller EAC. The content of the action isset to store the position of the base station BST in the database DB onreceipt of TG-1 data whose tag ID indicates Mr. Suzuki,

An information link pointer corresponding to the object OBJ-1 of thereal-world model list MDL will be set regarding the substance of thedata “Mr. Suzuki's position” stored in the database DB of thedistributed data processing server DDS-1.

Or, with regards to the object OBJ-2 of “Mr. Suzuki's seating,” themodel manager MMG issues a command to the distributed data processingserver DDS-1 to write a value of “00” in the database DB of thedistributed data processing server DDS-1 if the measurement of thewireless sensor node WSN-0 with a pressure switch as a sensor SSR is ON,and to write a value of “01” in the database DB of the distributed dataprocessing server DDS-1 if the measurement of the wireless sensor nodeWSN-0 is OFF.

Upon receipt of this command, the event action controller EAC of thedistributed data processing server DDS-1 proceeds to an operation ofwriting “00” or “01” for the measured data of the sensor node WSN-0(corresponding respectively ON or OFF) in the database DB of thedistributed data processing server DDS-1.

In the same way as described above, an information link pointercorresponding to the object OBJ-2 of the real-world model list MDL willbe set regarding the substance of the data “Mr. Suzuki's seating” storedin the database DB of the distributed data processing server DDS-1.

In this way, the object (information link pointer) set by the modelmanager MMG and the position of the distributed data processing serverDDS for actually storing the information are set.

As FIG. 14 shows, the model manager MMG creates the object OBJ-1 of “Mr.Suzuki's position” and stores the model name, the data ID and theinformation link pointer attached to the measured data of the sensornode in the real-world model list MDL. When the registration of theobject is completed, the model manager MMG sends a notice of completionto the service operation terminal ADT-B.

For displaying the notice of completing the creation of the objectsreceived and for creating the object, the service operation terminalADT-B repeats the operation described above to create the desiredobjects.

<Definition of the Model Binding List>

Then, after the creation of plural objects by the definition of themodel list MDL described above, we will describe the process of settingthe model binding list MBL showing the relationship of correspondenceamong plural objects OBJ-1 to OBJ-n with reference to FIG. 19.

In FIG. 19, the service manager accesses the model manager MMG of thedirectory server DRS from the service operation terminal ADT-B to accessthe retrieval interface of the model manager MMG. Then, the servicemanager retrieves the desired objects and returns the object matchingthe retrieval conditions to the service operation terminal ADT-B.

The service operation terminal ADT-B outputs the retrieval result of theobjects received from the model manager MMG on a display device notshown and the like.

The service manager selects a desired object from among the objectsdisplayed in the service operation terminal ADT-B and requests the modelmanager MMG of the directory server DRS to indicate the elements commonto all the objects in a model binding list.

For example, as FIG. 15 shows, the personal name “Mr. Suzuki” will becreated in the model binding list MBL-P, and this model binding listMBL-P will be related with the position of Mr. Suzuki OBJ-1, the seatingstate of Mr. Suzuki OBJ-2, and the temperature of Mr. Suzuki OBJ-3.

The model manager MMG relates the model binding list MBL-P with theinformation link pointer of all the objects OBJ-1 to OBJ-3 and storesthe same in the model binding list MBL.

When the registration of the model binding list MBL is completed, themodel manager MMG sends a notice of completion to the service operationterminal ADT-B.

For displaying the notice of completing the creation of the modelbinding list received and for creating the model binding list, theservice operation terminal ADT-B repeats the operation described aboveto create the desired model binding list.

<Retrieval of the Model Binding List>

We will then describe an example of the process of a user of the sensornetwork referring the data of the sensor node using the model bindinglist MBL with reference to FIGS. 20 and 21.

In FIG. 20, the user terminal UST accesses the search engine SER of thedirectory server DRS, and requests the model binding manager MBM toretrieve the model binding list MBL. This request for retrieval is made,for example, by the retrieval of key words and GUI as shown in FIG. 15.

The model binding list manager MBM returns the result of retrievalrequested to the user terminal UST and displays the result of the modelbinding list matching with the retrieval request on a display device ofthe user terminal UST.

The user selects any model binding list from among the retrieval resulton the user terminal UST and requests information (Step 110).

Here, as FIG. 15 shows, the model binding list is constituted by linkpoints in a tree structure grouped together by common elements among theobjects OBJ, and the users present their request for information to thedistributed data processing server DDS constituting the link pointer bychoosing any link pointer displayed in the model binding list of theuser terminal UST.

In the distributed data processing server DDS, the user accesses themeasured data or secondary data requested from the user terminals USTand returns the access result to the attribute interpretation listmanager ATM of the directory server DRS.

In the directory server DRS, the attribute interpretation list managerATM obtains the meaning for the return value of the attributeinterpretation list ATL shown in FIG. 13 from the data ID of themeasured data sent from the distributed data processing server DDS (Step112).

Then, the search engine SER of the directory server DRS returns themeaning corresponding to the measured data analyzed by the attributeinterpretation list manager ATM to the user terminal UST, and the userterminal UST displays the response of the directory server DRS in theplace of the response from the distributed data processing server DDS.

For example, when the link pointer LINK-1 of the model binding listMBL-P shown in FIG. 15 is chosen, the measured data of the distributeddata processing server DDS-1 set previously for the position of Mr.Suzuki OBJ-1 from the user terminal UST is accessed. If the link pointerLINK-1 is related for example with the data link pointer of the sensorinformation table STB shown in FIG. 12, the distributed data processingserver DDS reads the measured data of the mobile sensor node MSN-1 beingthe measured data from the database DB corresponding to this data linkpointer, and returns to the directory server DRS.

In the directory server DRS, the place table ATL-p of the attributeinterpretation list ATL is chosen from data attribute stored togetherwith data, and the meaning corresponding to the return value(measurement) is acquired. In this case, as shown in FIG. 21, if thereturn value is 02 for example, the information of the link pointerLINK-1 of the model binding list MBL-P will be “meeting room A.”Therefore, the response for the object OBJ-1 of “Mr. Suzuki's position”of the model binding list MBL-P is converted from a measurement value ofthe sensor node MSN-1 “02” into the meaningful information “meeting roomA” and will be displayed (or notified) on the user terminal UST.Incidentally, the present embodiment shows the method wherein the dataattribute will be acquired together with the data. In this case, thedata link pointer and their attribute of sensor node are set, at thetime of registration, to the distributed data processing server DDS thatis to receive data from the sensor node. As another method of acquiringdata attribute, attributes may be designated to models at the time ofregistering the real-world model list MDL.

FIG. 22 shows the case of carrying out the operation of FIG. 20 abovefor “the seated state of Mr. Suzuki” LINK-2 of the model binding listMBL-P shown in FIG. 15. In this case also, the return value “00” fromeach wireless sensor node WSN-3 to WSN-10 is read from the distributeddata processing server DDS, and in the attribute interpretation listmanager ATM of the directory server DRS, the return value=“00” will be“present” and a meaningful information that “Mr. Suzuki is present” canbe returned from the search engine SER to the user terminal UST.

FIG. 23 shows the case of carrying out the operation of FIG. 20 abovefor “the temperature of Mr. Suzuki” LINK-3 of the model binding listMBL-P shown in FIG. 15. In this case also, a return value “x” from thesensor SSR-1 of each wireless sensor node MSN-1 is read from thedistributed data processing server DDS, and a return value=x iscalculated as temperature y=f (x) in the attribute interpretation listmanager ATM of the directory server DRS, and a meaningful piece ofinformation that “the ambient temperature around Mr. Suzuki is y ° C.”can be returned from the search engine SER to the user terminal UST.

FIG. 24 shows the case of carrying out the operation of FIG. 20 abovefor “the members in the meeting room A” of the model binding list MBL-Rshown in FIG. 15. In this case, when an object formed of the members ofthe meeting room A OBJ-4 is created in the model manager MMG, in thepredetermined distributed data processing server DDS-1, the tag ID ofthe identification card node detected by the base station BST-1corresponding to the meeting room A is read in the base station BST-1 asmeasured data. And this value will be stored in the information linkpointer shown in FIG. 14 (here, the distributed data processing serverDDS-1) set in advance as a data link pointer.

The distributed data processing server DDS-1 collects at a prescribedfrequency the tag ID of the wireless sensor nodes MSN-1 to MSN-n fromthe base station BST-1 and updates the value showing the members of themeeting room A (set of tag ID of the identification card nodes). FIG. 24shows that the employees whose tag ID are “01” and “02” have beendetected in the meeting room A from the wireless mobile sensor nodesMSN-1 to MSN-n collected by the distributed data processing serverDDS-1.

The distributed data processing server DDS-1 transmits this secondarydata “01. 02” to the attribute interpretation list manager ATM of thedirectory server DRS.

The attribute interpretation list manager ATM of the directory serverDRS converts the secondary data received into meaningful information of01=Suzuki and 02=Tanaka with reference to the personal name table ATL-mdefined in advance and send the same to the user terminal UST.

As a result, on the user terminal UST, meaningful information that “Mr.Suzuki and Mr. Tanaka are in the meeting room A” can be obtained inresponse to the request for information on the members in the meetingroom A of the model binding list MBL-P.

FIG. 25 shows the case of carrying out the operation shown in FIG. 20above for “the number of persons in the meeting room A” of the modelbinding list MBL-R shown in FIG. 15. In this case, when an object formedof the number of persons in the meeting room A OBJ-5 is created in themodel manager MMG, in the predetermined distributed data processingserver DDS-1, the number of persons in the meeting room A, specificallythe number of IDs of the identification card detected by the basestation BST-1 corresponding to the meeting room A or the number of theseating detection nodes which is ON is calculated. And this value willbe stored in the information link pointer shown in FIG. 14 set inadvance as a data link pointer of the object OBJ-5.

The distributed data processing server DDS-1 collects the number x ofthe data IDs of the wireless mobile sensor nodes MSN-1 to MSN-n from thebase station BST-1 at a prescribed frequency, and calculates and updatesthe value showing the number of persons at the meeting room A (secondarydata). The distributed data processing server DDS-1 sends this secondarydata x to the attribute interpretation list manager ATM of the directoryserver DRS.

The attribute interpretation list manager ATM of the directory serverDRS converts the received secondary data into meaningful information ofa number of person y=x from the number of person table ATL-n defined inadvance and send the same to the user terminal UST from the searchengine SER.

As a result, it is possible to acquire a meaningful piece of informationthat “there are y persons in the meeting room A” in response to arequest for information for the number of persons in the meeting room Aof the model binding list MBL-P at the user terminal UST.

<Action Controller>

FIG. 26 is a block diagram showing the details of the action controllerACC of the directory server DRS.

Based on a notice on the occurrence of an event received from the eventaction controller EAC of plural distributed data processing servers DDS,the action controller ACC automatically performs an “action” previouslyset.

Accordingly, the action controller ACC includes an action receiver ARCfor receiving the setting of action from the user terminal UST throughthe session controller SES, an action analyzer AAN for analyzing theaction received and for setting the distribution of functions (or loads)between the directory server DRS and the distributed data processingserver DDS according to the analysis result, an action manager AMG formanaging the definition and execution of actions, an action table ATBfor storing the relationship between the events and actions according tothe request for setting from the user terminal UST, an event monitorinstructor EMN for issuing instructions to the distributed dataprocessing server DDS-1 to DDS-n to monitor the events defined in theaction table ATB, an event receiver ERC for receiving the notice ofevents that occurred at each distributed data processing server DDS-1 toDDS-n, and an action executer (executing unit) ACEC for executing thepreset actions based on the definition of the event-action table ATBreceived.

The action executer ACEC constituting the action controller ACC isconstructed as shown in FIG. 27. In FIG. 27, the action executer ACECincludes an action dispatcher ADP that receives event occurrencenotification from the action manager AMG of FIG. 26, reads the contentof action corresponding to the data ID in which the event occurrencenotification originates, and action execution parameters from the actiontable ATB, and issues commands to processors described later.

The above-mentioned processors that execute specified action uponreceipt of a command from the action dispatcher ADP include anotification and forwarding processor NTC that performs communicationwith a user terminal and the like, a storing processor LDP that storesdata in a latest data memory LDP-D as action, and a secondary dataprocessor DPR that processes data as action.

The notification and forwarding processor NTC includes protocolcontrollers corresponding to the content of action, to perform pop-upnotification and Email transmission to the user terminal UST and thelike. For example, it performs pop-up notification and data forwardingby SIP (Session Initiation Protocol), transmits Email by SMTP (SimpleMail Transfer Protocol), and transmits data described by HTML (HyperText Markup Language) and the like.

The storing processor LDP stores data specified in action in a datamemory LDP-D included in the directory server DRS. The data memory LDP-Dincluded in the directory server DRS allows the latest data to beprovided according to access from the user terminal UST, andcorrespondence relations between the data memories LDP-D and objects areset in advance in the real-world model table MTB.

The secondary data processor DPR performs a specified operation on datafrom the distributed data processing server DDS and the like to generatesecondary data. It adds a data ID to the secondary data. The secondarydata can be transmitted to the latest data memory LDP-D and otherdistributed data processing servers DDS.

The notification and forwarding processor NTC, the storing processorLDP, and the secondary data processor DPR can communicate with the firstnetwork NWK-1 through the network interface NIF to transmit and receivedata and transmit messages.

On receiving the event occurrence notification from the action managerAMG, the action dispatcher ADP reads action and parameters thatcorrespond to the data ID in which the event originates, from the actiontable ATB.

The action dispatcher ADP decides to which processor a command is to beissued, from the content of the action, and issues commands (includingparameters if necessary) to the secondary data processor DPR, thenotification and forwarding processor NTC, and the storing processorLDP.

The registration of actions is explained with reference to the timingchart in FIG. 28. In FIG. 28, in the beginning, the user (or the servicemanager) accesses the action controller ACC of the directory server DRSthrough the user terminal UST or the like to request the setting ofaction. For example, as an example of action shown in FIG. 29, we willexamine the case where Mr. X taking his seat triggers sending a pop-upnotice to the IP address of the user terminal UST of A.

Upon receipt of this request for action setting, the action receiver ARCof the action controller ACC requests to the action analyzer AAN to setthe action. For instance, when there is a request for Mr. X taking hisseat from the user terminal UST, the action analyzer AAN selects, fromthe real-world model list MDL, the data ID of the sensor node to bemonitored through the model name of Mr. X taking his seat, and determinethe event condition of the measured data of the sensor node. Here, inorder to convert the real-world event of “Mr. X taking his seat” into adata ID, the return value that means the model of “Mr. X taking hisseat” and the person's presence (being seated) will be retrieved byreferring the real-world model list MDL of the real-world model tableMTB and the attribute interpretation list ATL. That is, the meaning ofthe model name which the user can understand is converted to the ID andlocation of the sensor node and the return value.

Here, if Mr. X=Mr. Suzuki as shown in FIG. 30, the model is alreadydefined in the real-world model table MTB, the data ID=X2 and theinformation link pointer (the distributed data processing server DDS1)for storing the data will be acquired from the lists MDL and ATLmentioned above.

Then, the action manager AMG sends an instruction to the distributeddata processing server DDS to be the data link pointer corresponding tothe model name chosen as described above to monitor the occurrence of anevent of “Mr. X taking seat” in order to monitor the occurrence of anevent “Mr. X taking his seat” by the distributed data processing serverDDS. Upon receipt of the instruction of the action manager AMG of thedirectory server DRS, as shown in FIG. 31, with regards to the dataID=X2 acquired from the real-world model list MDL, the distributed dataprocessing server DDS registers the condition “00” for taking seatacquired from the attribute interpretation list ATL and the actioncontroller ACC of the directory server DRS registers as the recipient ofthe notice of an event to be undertaken for an action. Incidentally, thenotice to be given to the directory server DRS is an action executed inthe distributed data processing server DDS-1. And the action manager AMGsets an action of “IP address: send a pop-up notice to the user terminalUST of A” in the action table ATB shown in FIG. 32, and sets the sensornode ID mentioned above as an ID of the event of executing the action.

In other words, in the event table ETB of the distributed dataprocessing server DDS shown in FIG. 31 the data ID=X2 with a pressuresensor showing “Mr. Suzuki seated” will be set in the data ID columnshowing the ID of the measured data, the value of X2 data “00”indicating the seating state will be set in the event condition column,and the action of notifying to the action controller ACC of thedirectory server DRS will be set in the action column of the distributeddata processing server DDS-1.

As is shown in the action table ATB of the directory server DRS shown inFIG. 32, the data ID=X2 indicating that “Mr. Suzuki is seated” will beset in the data ID column showing the event ID of the object ofmonitoring, the reception of the occurrence of an event from thedistributed data processing server DDS-1 will be set in the eventcondition column, a pop-up notice to the user terminal UST will be setin the action column to be executed by the directory server DRS, and theIP address indicating Mr. A from among the user terminal UST will be setin the action parameters column.

The action to be registered by the action manager AMG in the actiontable ATB will be, as shown in FIG. 32, conditioned by the reception ofthe event occurrence of data ID=X2, and the action of a pop-up noticewill be set to be sent to the address (here the terminal of the IPaddress) entered in the parameter column.

On the other hand, the screen for requesting the action setting in FIGS.28 and 29 is provided by the action receiver ARC of the directory serverDRS to the user terminal UST, and the real-world model list MDL isrelated to the “personal name” pull-down menu, the pull-down menu“seated,” “in conference” and “at home” is related with the attributeinterpretation list ATL, and the pull-down menu of “pop-up” and “mail”shows the action to be executed by the directory server DRS.

A single action to be executed following a single event as describedabove will be called “a single action,” as is shown in FIG. 33. In otherwords, when a request for an event and action setting with the semanticinformation that the user can understand is presented by the userterminal UST to the action controller ACC of the directory server DRS,an action analysis and an instruction for monitoring an event,corresponding to the semantic information, are created in the actioncontroller ACC, and an event table ETB will be defined in theevent-action controller EAC of the distributed data processing serverDDS. Then, the action manager AMG of the action controller ACC instructsthe event receiver ERC to monitor the event set above (data ID=X2), andsets the action (pop-up notice) requested by the user to the actiontable ATB. By this action, the action controller ACC informs the userterminals UST that a series of action settings have been completed.

<Execution of Actions>

FIG. 34 is a time chart showing the execution of single actions set inFIGS. 28 and 29 above.

When the measured data value of the sensor nodes monitored changes to“00”, which is the conditions of event occurrence meaning that Mr. X hastaken seat has been determined, the distributed data processing serverDDS-1 generates an event notice relating to the data ID=X2.

This event occurrence will be notified by the distributed dataprocessing server DDS to the directory server DRS and will be receivedby the even receiver ERC shown in FIG. 26.

The action manager AMG of the directory server DRS retrieves the actiontable ATB shown in FIG. 32 from the event ID received and judges whetherthere is any pertinent action or not. As the ID=X2 event received isdefined in the action table ATB, the action manager AMG informs theaction executer ACEC on the action and parameters of the action tableATB.

The action executer ACEC executes processing corresponding to adefinition based on the notice instructed by the action manager AMG. Inthis case, the action executer ACEC sends a pop-up notice to the userterminal UST having an IP address A that is designated by the actionmanager AMG. The pop-up notice is sent to the user UST with IP address Aenabling to confirm that Mr. X has taken his seat.

<Setting and Execution of Action from Plural Events>

FIGS. 29, 30 and 34 describe the case of taking an action for an eventthat has occurred. However, as shown in FIGS. 35 to 41, it is possibleto set the case of taking an action when two events have occurred.

FIGS. 35 and 36 are screens for requesting the setting for an actiontriggered by plural events occurrence. In this screen for requestingsetting, a pull-down menu wherein the state of “being seated” and thelike for two personal name columns can be chosen is defined. Theconditions for the event corresponding these two personal names are,like FIGS. 28 and 29 above, related with the real-world model list MDLand the attribute interpretation list ATL of the real-world model tableMTB.

Moreover, a pull-down menu for setting the Boolean expression (AND, OR)of the event conditions of these two persons will be added.

Just like the single action mentioned above, the action to be executedby the directory server DRS (pop-up notice, mail transmission) and theparameters column (address and the like) required for the execution ofthe actions will be set.

Here, we will describe the case of action of sending Email when theevent of the distributed data processing server DDS-1 of “Mr. Suzukitaking seat” has occurred and the event of the distributed dataprocessing server DDS-2 of “Mr. Tanaka taking seat” has also occurred.

To begin with, the event of “Mr. Suzuki taking seat” will be set in thesame way as FIGS. 29 and 30 above, and the event shown in FIG. 37 willbe set in the event table ETB of the distributed data processing serverDDS-1 which monitors the taking seat of Mr. Suzuki. The time chart ofsetting the action table at this time will be shown in FIG. 40.

Then, with regard to the event of “Mr. Tanaka taking seat,” like FIGS.29 and 30 shown above, the data ID=Y2 for detecting Mr. Tanaka's takingseat will be set in the data ID column, and “00” showing the taking seatfrom the attribute interpretation list ATL will be the condition of theevent, and the action of informing the action controller ACC of thedirectory server DRS when this event condition has been met will be setin the event table ETB of the distributed data processing server DDS-2as shown in FIG. 38.

In the action controller ACC of the directory server DRS, as shown inFIG. 39, two conditions will be combined by the Boolean expression of“AND” in the action table ATB and will be set.

Regarding the two conditions of the action table ATB combined by “AND,”“Email transmission” will be set in the action column and the address ofthe addressee (Mr. B's Email address) will be set in the parametercolumn.

In the time chart in FIG. 40, like FIG. 33 above, requests for settingthe action related with Mr. Suzuki's seating and Mr. Tanaka's seatingare presented from the user terminal UST to the action controller ACC,and a request for setting is presented from the event monitor instructorEMN to the distributed data processing server DDS-1 to inform the eventwhen the measured data of the sensor node with a data ID=X2 hassatisfied the prescribed condition (Mr. Suzuki taking place), and arequest for setting is presented from the event monitor instructor EMNto the distributed data processing server DDS-2 to inform the event whenthe measured data of the sensor node with a data ID=Y2 has met theprescribed condition (Mr. Tanaka taking place).

In the distributed data processing servers DDS-1 and 2, new events areadded to the respective event table ETB, and the event condition parserEVM of each distributed data processing server DDS-1 and 2 startmonitoring events for the measured data.

In the action manager AMG of the action controller ACC, the eventreceiver ERC is instructed to monitor the events with data ID=X2 and Y2and the setting action is completed.

Then, FIG. 41 is a time chart showing how the actions are executed.

At the beginning, the distributed data processing server DDS-1 generatesthe events of data ID=X2 as Mr. Suzuki takes his seat. While the actioncontroller ACC receives the event with data ID=X2, the action table ATB,being unable to execute any action until Mr. Tanaka takes his seat,withholds any relevant action.

Then, the distributed data processing server DDS-2 generates the eventsof data ID=Y2 as Mr. Y takes his seat. The action controller ACCreceives the event of the data ID=Y2, and as the AND condition of thedata ID=X2 and Y2 is satisfied in the action table ATB, the action isexecuted and the Email is transmitted to the predetermined mail address.

In this way, actions can be executed on the condition that plural eventsoccur, and responses necessary for the user can be obtained from a largenumber of sensors. Accordingly, even if there are a huge number ofsensor nodes, the users can detect almost in real time the desiredinformation (or changes in information) and the information of thesensor nodes can be used effectively.

SECOND EMBODIMENT

FIGS. 42 to 46 show a second embodiment, indicating how single actionsare executed in the distributed data processing servers DDS. An actionexecuter ACE is added to the event action controller EAC of thedistributed data processing server DDS in FIG. 9, the event table ETBshown in FIG. 9 is replaced by the event action table EATB. The rest ofthe structure is the same as the first embodiment. The event-actiontable EATB is a combination of the event table ETB of the firstembodiment and the action table ATB.

In FIG. 42, the event action controller EAC of the distributed dataprocessing server DDS includes an event action table EATB for relatingthe measured data collected from the base stations BST with the eventsand actions through the directory server interface DSI.

As FIG. 44 shows, each record of the event-action table EATB includesdata ID given to the measured data allocated to each sensor node, anevent contents column indicating the conditions on the measured data forgenerating events, an action column indicating the details of the actionexecuted by the distributed data processing server DDS when an eventoccurs, a parameter column for storing the values necessary forexecuting an action, a data holder DHL for determining whether themeasured data will be stored in the database DB or not when an eventoccurs.

For example, in the figure, the measured data having data ID=X1 are setin such a way that when their value is “02”, Email will be transmittedto the address specified in the parameter column. The measured data willnot be written in the disk drive DSK even if the condition is met whenan event occurs.

The following describes the function of the event-action controller EACshown in FIG. 42. Measured data received from the base station BST getsthe data ID extracted in the sensing data ID extractor IDE. At the sametime, the sensing data ID extractor IDE sends the measured data to thelatest data memory LDM.

The extracted data ID will be sent to the event search engine EVS. Theevent search engine EVS searches the event action table EATB. If arecord whose data ID matches is found, the EATB sends the event entry ofthe record and the parameter to the event condition parser EVM.

The event condition parser EVM compares the value of measured data andthe event entry EVT, and if they meet the conditions they will be sentto the action executer ACE.

The action executer ACE reads the content of the action set in theevent-action table EATB to execute predetermined processing such aswriting data into the DB controller DBC (or disk DSK), notifying theuser terminal UST, and performing operations on measured data.

The database controller DBC will write, of the measured data of whichevents occurred, the data whose data holder DHL is YES in the eventaction table EATB in the disk drive DSK.

The data access receiver DAR is similar to the embodiment 1 describedabove, and if the access request is for the latest data, it will readthe measured data matching the data ID contained in the access requestfrom the latest data memory LDM and return the same to the networkprocessor NWP.

FIG. 45 shows a time chart for setting actions in the distributed dataprocessing server DDS and FIG. 43 shows an example of interface sent bythe action controller ACC of the directory server DRS to the userterminal UST for setting actions. Incidentally, at the time of setting asingle action, the directory server DRS communicates with thedistributed data processing servers DDS and sets the request for settingactions received from the user terminals UST to the distributed dataprocessing server DDS corresponding to the data ID designated.

To begin with, the user (or the service manager) accesses the actioncontroller ACC of the directory server DRS from the user terminal USTand the like and requests to set actions. As an example of actions, wewill examine the case of, as FIG. 29 shows, setting actions ofmonitoring the position of Mr. X and upon his entry into the meetingroom A, sending a pop-up notice to the user terminal UST with an IPaddress: A.

Upon receipt of this request for setting action, the action receiver ARCof the action controller ACC requests the action analyzer AAN to set theaction. The action analyzer AAN chooses the data ID of the sensor nodeof the object of monitoring from, for example, Mr. X's position, anddecides in which condition of the measured data of the sensor node theevent will occur. Here, in order to convert the real-world event of “Mr.X taking his seat” into a data ID of a sensor node, it will search themodel of “Mr. X taking his seat” by referring to the real-world modellist MDL and the attribute interpretation list ATL (semantic informationmanagement table) of the real-world model table MTB.

Here, as shown in FIG. 31, if Mr. X=Mr. Suzuki, the model has alreadybeen defined in the real-world model table MTB, the information linkpointer for storing the data ID=X2 and the data (distributed dataprocessing server DDS1) will be acquired from the lists mentioned aboveMDL and ATL.

Then, the action manager AMG judges whether the request presented by theuser terminal UST is for a single action or not, and if it is for asingle action, it will set in such a way that the requested actionrequested may be executed in the distributed data processing server DDSwhich holds the information mentioned above.

To generate the event of the “location of X” and action in thedistributed data processing server DDS, a command to generate the eventthat the “location of X” is a “meeting room A” is issued to thedistributed data processing server DDS that manages the above-mentionedselected sensor node. And the action controller ACC of the directoryserver DRS sets the action of “sending Email to the user with a mailaddress: mailto_b@xyz.com” in the event-action table EATB in thedistributed data processing server DDS, and sets the data ID of thesensor node mentioned above as the event ID for executing the action.

The distributed data processing server DDS having received theinstruction from the action manager AMG of the directory server DRSregisters, as shown in FIG. 44, the condition “02” for the meeting roomA acquired from the attribute interpretation list ATL relating to thedata ID=X1 acquired from the real-world model list MDL and the Emailaddress mentioned above for the recipient of the action.

The action of registering by the action manager AMG in the distributeddata processing server DDS will be set, as shown in FIG. 43, in such away that the action of sending Email may be executed to the addressentered in the parameter column when the event whose data ID=X1 occurs.

Thus, when the user terminal UST presents a request for setting a singleaction, the action controller ACC of the directory server DRS setsvalues on the corresponding distributed data processing server DDSinstead of setting values in its own action table ATB so that bothevents and actions may be set in the event-action table EATB of thedistributed data processing server DDS.

The events and actions will be executed in the distributed dataprocessing server DDS as shown in FIG. 46. When Mr. X enters the meetingroom, the value whose data ID=X1 will be “02” and the event occurrencedefined in the event-action table EATB shown in FIG. 44 will bemonitored and the resulting actions will be taken. As a result of theexecution of the action, the entry of Mr. X into the meeting room A willbe notified to the prescribed Email address.

In this case, the directory server DRS only sets actions to thedistributed data processing server DDS, and it is not necessary tomonitor the actual occurrence of events. Accordingly, the collection ofdata and the execution of single action may be entrusted to thedistributed data processing servers DDS, and the directory server DRSonly does tasks such as monitoring the request for retrieval and pluralactions with plural events from the user terminals UST. Therefore, whenthe number of sensor nodes is very large, it is possible to prevent theoverloads of the directory server DRS and to operate the sensor networksmoothly.

In the above-mentioned second embodiment, an example of setting eventsand actions in the event-action table EATB of the distributed dataprocessing server DDS is shown. However, an event table that storesevents, and an action table that stores actions may be made independentof each other.

THIRD EMBODIMENT

FIGS. 47 to 53 show a third embodiment. In this embodiment, secondarydata outputted from the action executer ACE of the distributed dataprocessing server DDS of the second embodiment is inputted to thesensing data ID extractor IDE, and a next event and action arecontinuously executed in one distributed data processing server DDS,based on the secondary data. The third embodiment is the same as thesecond embodiment in other constructions.

The action executer ACE constituting the event-action controller EAC isconstructed as shown in FIG. 48. In FIG. 48, the action executer ACEincludes: an action dispatcher ADP that receives event occurrencenotification from the event condition parser EVM of FIG. 47, measureddata (raw data, secondary data) from the sensing data ID extractor IDE,and action and parameter from the event-action table EATB, and issuescommands to other processors described later; a notification andforwarding processor NTC that performs communication with a userterminal and the like as action; a disk storing processor LDM-D thatstores data in a latest data memory LDM and disk DSK as action; and asecondary data processor DPR that processes data as action.

The notification and forwarding processor NTC includes protocolcontrollers corresponding to the content of action, to perform pop-upnotification and Email transmission to the user terminal UST and thelike. For example, it performs pop-up notification and data forwardingby SIP, transmits Email by SMTP, and transmits HTML data by HTTP.

The disk storing processor LDM-D includes a memory interface foraccessing the latest data memory LDM, and writes data to the latest datamemory LDM. Moreover, based on the setting of the event-action tableEATB, it stores data written to the latest data memory LDM in a disk DSKthrough the DB controller DBC.

The secondary data processor DPR performs an operation specified inparameters and the like on data from the sensing data ID extractor IDEand generates secondary data. It adds a data ID to the secondary data.

Output of the secondary data processor DPR is connected to the sensingdata ID extractor IDE by the loop-back path RP shown in FIG. 47.Secondary data processed in the secondary data processor DPR issubjected to event-action processing just like measured data (raw data)from a sensor node.

On receiving event occurrence notification from the event conditionparser EVM, the action dispatcher ADP receives the data in which theevent occurs from the sensing data ID extractor IDE, and reads actionand parameter corresponding to the data ID, and information indicatingwhether to store the data in a disk.

The command and data of the action dispatcher ADP are inputted to thesecondary data processor DPR, forwarding processor NTC, and disk storingprocessor LDM-D. Data or a parameter is transmitted to these processorsin accordance with the content of action set in the event-action tableEATB.

As shown in FIG. 47, the action executer ACE of the distributed dataprocessing server DDS, when a new action is data processing, performsspecified data processing in the above-mentioned secondary dataprocessor DPR, and adds a data ID to the processing result before inputto the sensing data ID extractor IDE. Since different processors of theaction executer ACE are independent of one another, it can performplural actions at the same time.

By this construction, as shown in FIG. 49, plural actions can beexecuted in a chain beginning with one action (event occurrence) toprocess measured data or further process secondary data.

In FIG. 49, for example, with a sensor node as a temperature sensor, asecondary data action 210 that converts measured data of data ID=X1 fromCentigrade scale into Fahrenheit scale and adds a new data ID=X2, and anotification action 220 that performs notification processing based onsecondary data converted into Fahrenheit scale can be continuouslyperformed in one distributed data processing server DDS.

When the processing shown in FIG. 49 is performed, an event-action tableEATB is set, for example, as shown in FIG. 50.

The event-action table EATB of the third embodiment is provided withplural action fields corresponding to the number of processors(secondary data processor DPR, notification and forwarding processorNTC, and disk storing processor LDM-D) of the action executer ACE, andplural actions can be defined for one data ID. In FIG. 50, three actionfields—secondary data processing, data forwarding processing, andnotification processing—are provided. Each action field is provided withan optional parameter field to store a parameter required for actionexecution.

As an example of processing of FIG. 49, in an entry of data ID=X1 ofFIG. 50, data arrival (receive) is set as event condition, and theaction field of data processing is specified so that when measured datais received from a sensor node, the unit of the measured data isconverted from Centigrade temperatures into Fahrenheit temperatures. Asan option of data processing of the unit conversion, the parameter fieldis set so as to specify the data ID of secondary data newly generated as“X2.”

As action performed after the data processing, “loop-back” is set in theforwarding field so that produced secondary data is inputted to the dataID extractor IDE. In the case of loop-back, since a forwardingdestination is the distributed data processing server DDS, the parameterfield in the forwarding field is blanked (a forwarding destination doesnot need to be specified). Since notification processing is notperformed in the event action of data ID=X1, the notification processingfield is blanked.

By this entry, in the distributed data processing server DDS, whenmeasured data of data ID=X1 is received, as event occurrence and action,unit conversion from Centigrade scale to Fahrenheit scale is performedto produce secondary data of data ID=X2 and input it to the data IDextractor IDE.

Next, the entry of the produced secondary data is set in theevent-action table EATB as data ID=X2. An example of event condition isthat when the value of data (Fahrenheit) inputted from the actionexecuter ACE exceeds 60, an event is generated. As action executed basedon this event occurrence, Email notification is set in the notificationprocessing field. The address of Email notification destination is setin the parameter field of the notification processing field. The contentof Email is set in advance; for example, “Temperature is too high” isset.

By this entry, in the distributed data processing server DDS, whensecondary data of data ID=X2 is inputted to the ID extractor IDE, if thevalue of the data exceeds 60° F., the action to transmit Email to aspecified notification destination is performed.

By the above-mentioned two entries, as shown in FIG. 49, on receivingCentigrade measured data, the distributed data processing server DDSgenerates secondary data converted into Fahrenheit, and further canperform the indicated action based on the value of the secondary data.That is, if the measured data received by the distributed dataprocessing server DDS is defined as primary data, and secondary datagenerated based on the primary data as secondary data, the distributeddata processing server DDS generates secondary and tertiary data fromthe primary data in the event-action table EATB, and can performforwarding and notification processing for the individual data inparallel.

An example of executing events and actions from one piece of measureddata in a chain has been described above. As shown in FIGS. 51 and 52,one distributed data processing server DDS can generate secondary data(secondary data) from plural pieces of measured data (primary data).

For example, in FIG. 51, discomfort index can be generated from outputof a temperature sensor and a humidity sensor. Data ID=Y1 is measureddata whose semantic information A is temperature, and data ID=Y2 ismeasured data whose semantic information D is humidity. On receivingthese measured data, the distributed data processing server DDSgenerates secondary data Y3 whose semantic information E is discomfortindex from the measured data of temperature and humidity (dataprocessing action 310), and further forwards the secondary data Y3 (dataforwarding action 320).

As an example of the processing of FIG. 51, the event-action table EATBis set as shown in FIG. 52. In the entry of data ID=Y1, data arrival(receive) is set in the event condition field, and the data processingfield of the action field is specified so that if measured dataindicating temperature is received from a sensor node, the measured datais held. The data holding denotes updating the value of the latest datamemory LDM each time measured data Y1 arrives.

In the entry of data ID=Y2 indicating humidity, data arrival (receive)is set in the event condition field, and the data processing field isspecified so that if measured data indicating humidity is received froma sensor node, the measured data Y1 indicating temperature and themeasured data DY2 indicating humidity are added to generate secondarydata indicating discomfort index as data ID=Y3. Furthermore, loop-backis set in the forwarding field.

In the entry of data ID=Y3 indicating discomfort index, data arrival(input) is set in the event condition field, and the forwarding field isspecified so that if secondary data indicating discomfort index isreceived, the secondary data Y3 is forwarded to the destination IPaddress “B.”

By setting the event-action table EATB as described above, secondarydata can be obtained from plural pieces of measured data (primary data),and further events and actions can be executed based on the secondarydata (secondary data).

Thus, in the event-action table EATB, ID (data ID) of a virtual sensornode is added to processed data, and an event action is defined for theID of the virtual sensor node. By inputting (looping back) the output ofthe action executer AEC to the sensing data ID extractor IDE, pluralactions can be executed in a chain from one piece of measured data toobtain secondary and tertiary data, or perform other processing.

By this construction, in one distributed data processing server DDS,since plural actions can be executed based on the reception of measureddata, it does not need to issue an inquiry to the directory server. DRSeach time an event occurs, and can perform processing independently ofother distributed data processing servers DDS. As a result, thedirectory server DRS and the network NWK-1 can be further reduced inload. In short, even in a sensor network that includes a lot ofdistributed data processing servers DDS, the load on communicationsbetween the directory server DRS and the distributed data processingservers DDS can be reduced, and at the same time the load (traffic) onthe network NWK-1 can be reduced, so that a large-scale sensor networkcan be smoothly managed.

The processing of FIG. 51 can be performed jointly by plural distributeddata processing servers DDS. For example, as shown in FIG. 53, each ofthree distributed data processing servers DDS-1 to DDS-3 may perform oneevent action.

In FIG. 53, the distributed data processing server DDS-1, to executeforwarding action 410, monitors measured data (ID=Y1) from a sensor nodethat measures temperatures, and on receiving measured data Y1, forwardit to the distributed data processing server DDS-3. The distributed dataprocessing server DDS-2, to execute forwarding action 420, monitorsmeasured data (ID=Y2) from a sensor node that measures humidity, and onreceiving measured data Y2, forwards it to the distributed dataprocessing server DDS-3.

The distributed data processing server DDS-3, like the entries of dataID=Y1 to Y3 in FIG. 52, holds measured data Y1 if receiving Y1, obtainthe sum of the measured data Y1 and Y2 when receiving Y2 as discomfortindex, and can execute other event and action 440 using secondary dataof data ID=Y3.

In this way, by acquiring plural pieces of data from other distributeddata processing servers DDS and generating secondary data, thedistributed data processing servers DDS that perform data processing,forwarding, and notification processing can be flexibly set orreconfigured, resulting in efficient resource utilization in the sensornetwork.

FOURTH EMBODIMENT

FIG. 54 shows a fourth embodiment. The fourth embodiment is the same asthe third embodiment, except that the construction of the actionexecuter ACE constituting the event-action controller EAC in thedistributed data processing server DDS is modified.

Output of the secondary data processor DPR that processes measured dataor secondary data is inputted to the data ID extractor IDE like thethird embodiment, and also inputted to the notification and forwardingprocessor NTC and the disk storing processor LDM-D. Commands and datafrom the action dispatcher ADP are inputted to the secondary dataprocessor DPR, the notification and forwarding processor NTC, and thedisk storing processor LDM-D.

Since the notification and forwarding processor NTC and the disk storingprocessor LDM-D are provided in subsequent stages of the secondary dataprocessor DPR, one occurrence of event enables plural actions to beexecuted. For example, in the event-action table EATB, like FIG. 50,three actions of data processing, data forwarding, and notificationprocessing as well as parameters corresponding to the actions aredefined. When an event occurs by receiving proper measured data, theaction dispatcher ADP commands the secondary data processor DPR to takeaction of data processing, commands the notification and forwardingprocessor NTC to take action of secondary data forwarding, and commandsthe disk storing processor LDM-D to store secondary data.

The secondary data processor DPR processes data, and outputted secondarydata is inputted to the notification and forwarding processor NTC, thedisk storing processor LDM-D, and the data ID extractor IDE. Thenotification and forwarding processor NTC transfers secondary data to aspecified address, and the disk storing processor LDM-D writes thesecondary data into the disk DSK.

By thus connecting in series processors of the action executer ACE, oneoccurrence of event enables plural actions to be executed so thatactions can be executed at high speed. By providing other processors insubsequent stages of the secondary data processor DPR, actions such asforwarding and storing for secondary data, which is generated after dataprocessing action, can be executed at one occurrence of event.

FIFTH EMBODIMENT

FIGS. 55 to 58 show a fifth embodiment. The fifth embodiment is the sameas the third embodiment, except that the event-action controller EAC ofthe distributed data processing server DDS is provided with anexceptional event-action table E-EATB that sets exceptional actions sothat the action executer ACE refers to the exceptional event-actiontable E-EATB.

The event-action table EATB is provided with an exception handling fieldas shown in FIG. 56. The exception handling field includes fields ofprocessing content and parameter. Processing content enables theexecution of program processing such as script processing that canexecute complicated processing that cannot be performed by simpleprocessing such as the above-mentioned data processing, forwarding, andnotification processing. In the option field, a file name for whichprocessing is described is set.

A file name set in the option field should be stored previously in theevent-action table EATB and the exceptional event-action table E-EATB.An example of exception handling described in XML script is shown inFIG. 57.

FIG. 57 shows an XML script file having a file name of C. Data of dataID=Z1 indicating temperature is acquired from a sensor node, and if thevalue of the data is not in the range of 10 to 20 degrees, a message “Itis too hot. The air-conditioner is on” is transmitted to a specifiedtransmission destination (IP address=133.144.xx.xx), and further an“activate” command to turn on the cooler is transmitted to equipmentdesignated as “cooler.com.”

FIG. 58 shows a flow of processing describing the above-mentionedexception handling. A request to register an event action is issued tothe directory server DRS from a user terminal UST, and at the same timea script file prepared in advance is sent there (500).

In the directory server DRS, the action controller ACC receives therequest to register an event-action, and acquires a script file. Theaction controller ACC analyzes requested semantic information referringthe real-world model table MTB, as shown in FIG. 33 of the firstembodiment, and sends the request to register an event-action and thescript file to a corresponding distributed data processing server DDS(510).

In the distributed data processing server DDS, the event-actioncontroller EAC registers the received script file in the exceptionalevent-action table E-EATB (520), and sets the requested event-action anda script file name registered in the parameter field of the exceptionhandling field in the event-action table EATB (530). It notifies thedirectory server DRS of registration completion (540).

The directory server DRS notifies the user terminal UST of theregistration completion of the event-action based on the notificationfrom the distributed data processing server DDS (550).

According to the event-action table EATB set as described above, thefollowing processing is executed in the distributed data processingserver DDS.

The event-action controller EAC monitors the data of data ID=Z1 from thesensor node. On receiving the data of Z1, to execute the scriptprocessing of the exception handling field, it reads the XML script fileof the file name C set in the option field from the exceptionalevent-action table E-EATB, and executes it in the action executer ACE.

In the case of the script shown in FIG. 57, the action executerdetermines whether the data of data ID=Z1 indicating temperatures is inthe range of 10 to 20 degrees, that is, an event occurs. When it isdetermined that an event occurs, according to the script, the action offorwarding the message “It is too hot. The air-conditioner is on” andthe action of activating the air-conditioner are executed.

As described above, complex processing can be performed by using programprocessing such as script. Therefore, complex and flexible processingcan be flexibly attained using measured data from sensor nodes.

The above-mentioned program processing is not limited to scripts; it maybe an executable file, etc.

An example of providing the exceptional event-action table E-EATB in adistributed data processing server DDS has been shown above. However,the exceptional event-action table E-EATB may be provided in the actioncontroller ACC of the directory server DRS. In this case, in the actioncontroller ACC of the directory server DRS, it becomes possible toexecute complex processing involving plural distributed data processingservers DDS.

<First Variant>

FIGS. 59 and 60 show a first variant. In the action controller ACC ofthe directory server DRS shown in the first embodiment, as shown in thethird or fourth embodiment, actions based on acquired data (or event)are performed in a chain. Other constructions are the same as those ofthe first embodiment.

Output of the action executer ACEC is transmitted to not only the userterminal UST but also the event receiver ERC. Specifically, the actionexecuter ACEC is constructed as shown in FIG. 60, and is different fromthat of FIG. 27 of the first embodiment in that output of the secondarydata processor DPR is connected to the event receiver ERC by a loop-backpath RP. Other constructions are the same as those of FIG. 27.

A virtual data ID (or an event ID) is added to secondary data generatedin the secondary data processor DPR, and is sent to the networkinterface NIF and the event receiver ERC.

On receiving the secondary data in the event receiver ERC, the actiondispatcher ADP acquires action previously set from the action table ATBbased on a virtual data ID and issues a command to a proper processor.

In this way, the action controller ACC of the directory server DRS canexecute action for data generated based on executed action.

<Second Variant>

FIGS. 61 and 62 show a second variant that is a variant of theabove-mentioned first or second embodiment. In this variant, measureddata from a certain sensor node is stored in a specified distributeddata processing server DDS as raw data A, and measured data from adifferent sensor node is stored in a specified distributed dataprocessing server DDS as raw data B.

Distributed data processing servers DDS subject processing (e.g.,average value of unit time) to raw data A (RDATA) and raw data B andstore the processing results in distributed data processing servers DDSas data A′ (PDATA) and data B′ (PDATB), respectively. The timing ofprocessing the raw data A and B may be performed as actions based onspecified conditions (time elapse) in the directory server DRS or eachdistributed data processing server DDS. When the processing of raw datais performed in distributed data processing servers DDS, data storagedestinations may be added to the event-action table EATB shown in FIG.44.

Moreover, a distributed data processing server DDS calculates third dataC (RDATC) from the processed secondary data A′ (PDATA) and B′ (PDATB) asa specified action, and stores new secondary data in a distributed dataprocessing server DDS. The result of processing on the third data C isstored as tertiary data C′ (PDATC).

For example, when raw data A is temperature and raw data B is humidity,secondary data A and B are the average temperature and average humidityof unit time, respectively. Moreover, discomfort index determined fromaverage temperature and average humidity can be obtained as third dataC, and the average value of third data C of unit time can be obtained astertiary data C′.

Though measured data is used as the timing of event occurrence in theabove-mentioned first or second embodiment, event generation and actionexecution can be performed from the secondary data A and B, third dataC, and tertiary data C′ as described above.

As shown in FIG. 62, if measured data (raw data) and secondary data arestored in one distributed data processing server DDS, the constructionof the real-world model table MTB in the directory server DRS can besimplified. In this case, the third data C obtained from the secondarydata A and B can be handled as raw data, and the tertiary data C′ can behandled as secondary data.

When operations from raw data to secondary data are performed in thedirectory server DRS shown in the first embodiment, like the firstvariant, output of the action executer ACEC of the directory server DRSmay be inputted to the event receiver ERC to add a virtual data ID tothe secondary data.

<Third Variant>

FIG. 63 shows a third variant. In the second or third embodiment, pluralsensor networks (NWK1 to NWK3) are connected and data is processed amongdistributed data processing servers DDS in different sensor networks.

In FIG. 63, distributed data processing servers DDS1-1 to DDS1-3 areconnected to a network NWK1. Plural sensor nodes (not shown in thedrawing) are connected to the distributed data processing servers DDS1-1to DDS1-3, respectively.

A distributed data processing server DDS2-1 is connected to a networkNWK2. A distributed data processing server DDS3-1 is connected to anetwork NWK3. Plural sensor nodes are connected to each distributed dataprocessing server DDS.

The event-action table EATB of the distributed data processing serverDDS1-1 in the network NWK1 is set so that measured data RDATA is storedin a disk when received, and forwarded to the distributed dataprocessing server DDS2-1 in the network NWK2.

The event-action table EATB of the distributed data processing serverDDS2-1 in the network NWK2 is set so that measured data RDATA, whenreceived, is subjected to specified processing to generate secondarydata PDATD, and the secondary data PDATD is stored in a disk andforwarded to the distributed data processing server DDS3-1 in thenetwork NWK3.

The event-action table EATB of the distributed data processing serverDDS1-2 in the network NWK1 is set so that measured data RDATB is storedin disk when received, and forwarded to the distributed data processingserver DDS3-1 in the network NWK3.

The event-action table EATB of the distributed data processing serverDDS3-1 in the network NWK3 is set so that secondary data PDATE iscalculated from the secondary data PDATD from the distributed dataprocessing server DDS2-1 and the measured data RDATB from thedistributed data processing server DDS1-2, and stored in a disk.

By the settings described above, the measured data RDATA measured in asensor node in the network NWK1 is forwarded to the distributed dataprocessing server DDS2-1 in the network NWK2 and processed as secondarydata PDATD, and then the secondary data PDATD is forwarded to thedistributed data processing server DDS3-1 in the network NWK3.

The measured data RDATB measured in a sensor node in the network NWK1 isforwarded to the distributed data processing server DDS3-1 in thenetwork NWK3.

The distributed data processing server DDS3-1 in the network NWK3calculates secondary data PDATE from the measured data RDATB from thenetwork NWK1 and the secondary data PDATD from the network NWK2, andstores it in a disk.

By thus defining the transmission and reception of data to and fromexternal networks NWK and data processing in the event-action tableEATB, data can be processed one after another while forwarding dataamong different sensor networks.

This construction, by extracting only necessary ones from among measureddata of an enormous number of sensor nodes in each sensor network andperforming necessary processing in each sensor network, enablesefficient transmission and reception of data by coupling plural sensornetworks.

<Fourth Variant>

In the first or second embodiment described above, the data link pointercorresponding to the model name was set as the information link pointerin the real-world model list MDL of the directory server DRS. However,the latest value of data may be stored in addition to the informationlink pointer.

In this case, the data traffic between the directory server DRS and thedistributed data processing server DDS increases as the number ofobjects increases. In view of the fact that, however, the data acquiredfrom each sensor is collected in a fixed frequency by the distributeddata processing server DDS, an excessive increase of the load for thenetwork NWK-1 is prevented, and it will be possible to respond quicklyto the request for data from the user terminal UST, resulting in furtherimprovement in response.

As described above, according to this invention, the directory servermanages collectively the location of data, plural distributed dataprocessing servers for collecting the data from the sensor nodes in realtime are provided and are distributed on the network, information ofdesired sensor nodes can be monitored real time by events and actions,it has become possible to use efficiently data received from a hugenumber of sensor nodes. Thus, this invention can be applied to a sensornetwork having a large number of sensor nodes.

While the present invention has been described in detail and pictoriallyin the accompanying drawings, the present invention is not limited tosuch detail but covers various obvious modifications and equivalentarrangements, which fall within the purview of the appended claims.

1. A sensor network system, comprising: distributed servers that processdata transmitted from sensor nodes; and a management server connectedwith the distributed servers through a network, wherein the managementserver comprises: a model list that stores preset model names; asemantic interpretation list that stores semantic informationcorresponding to a value of the data; and an event-action controllerincluding an action executer that executes processing previouslyspecified when an occurrence of an event is indicated from thedistributed servers, and the distributed servers comprise: an eventtable that stores monitoring conditions of values of data correspondingto the model names; and an event generator that receives datacorresponding to the model names from the sensor nodes, and notifies themanagement server of an occurrence of an event when receiving datasatisfying the monitoring conditions from the sensor nodes.
 2. Thesensor network system according to claim 1, wherein the model list ofthe management server further stores information storage destinations ofthe data corresponding to the model names, the management servercomprises: a receiver that receives a model name from a user terminal,and semantic information indicating a state of the model name; ananalyzer that refers to the model list based on the model name to selecta distributed server of information storage destination and data to bemonitored, and refers to the semantic interpretation list based on thesemantic information to decide a condition of data to be monitored; andan instructor that sends the selected monitoring object and the decidedcondition to the distributed server of the information storagedestination, and the distributed server stores the monitoring object andthe condition that are sent from the instructor, in the event table. 3.The sensor network system according to claim 1, wherein the managementserver manages identifiers added to data of the sensor nodes, the sensornodes transmit data including the identifiers, the distributed serverscomprise: an ID extractor that extracts the identifiers from datareceived from the sensor nodes; and an event search engine that searchesthe event table for the condition, based on the extracted identifiers,and the event generator compares the searched condition with the data todetermine whether the condition is satisfied, and when the condition issatisfied, generates an event.
 4. The sensor network system according toclaim 3, wherein the event-action controller includes a first actiontable that stores in advance processing performed when the condition issatisfied, correspondingly to the identifiers, and the action executerthat, when the event generator generates an event, performs processingstored in the first action table, based on the identifiers.
 5. Thesensor network system according to claim 3, wherein the action executer,when processing stored in the first action table is processing thatprocesses data transmitted from the sensor nodes, processes the data,adds an identifier to the processed data, and inputs the processed datato the ID extractor.
 6. The sensor network system according to claim 4,wherein the management server comprises: a receiver that receives amodel name from a user terminal, and semantic information indicating astate of the model name; an analyzer that refers to the model list basedon the model name to select a distributed server of information storagedestination and data to be monitored, and refers to the semanticinterpretation list based on the semantic information to decide acondition of data to be monitored; and an instructor that sends theselected monitoring object and the decided condition to the distributedserver of the information storage destination, the instructor notifiesthe event-action controller of the processing to be executed, based on arequest from the user terminal, and the event-action controller sets theprocessing to be executed in the first action table based on thenotification.
 7. The sensor network system according to claim 3, whereinthe event-action controller comprises: a first action table in whichfile names of files describing processing to be executed are specifiedcorrespondingly to the identifiers; and a second action table thatstores the files describing the processing to be executed, and theaction executer executes processing of files stored in the second actiontable, based on file names stored in the first action table based on theidentifiers.
 8. The sensor network system according to claim 7, whereinwhen executing a file stored in the second action table, the actionexecuter compares the condition with the data in place of the eventcondition parser to determine whether the condition is satisfied, anddecides processing to be executed when the condition is satisfied.
 9. Aprocessing method of data transmitted from sensor nodes, comprising:providing a model list that stores preset model names; providing asemantic interpretation list that stores semantic informationcorresponding to a value of the data; providing an event table thatstores monitoring conditions of values of data corresponding to themodel names; receiving data corresponding to the model names from thesensor nodes; notifiying an occurrence of an event when receiving datasatisfying the monitoring conditions from the sensor nodes; andexecuting processing previously specified when an occurrence of an eventis notified.
 10. The processing method of data according to claim 9,wherein the model list of the management server further storesinformation storage destinations of the data corresponding to the modelnames, and the method further comprising: receiving a model name from auser terminal, and semantic information indicating a state of the modelname; selecting a information storage destination and data to bemonitored by refering to the model list based on the model name,deciding a condition of data to be monitored by refering to the semanticinterpretation list based on the semantic information; and storing themonitoring object and the condition in the event table.
 11. Theprocessing method of data according to claim 9, further comprising:receiving data including identifiers from the sensor nodes; extractingthe identifiers from data received from the sensor nodes; searching theevent table for the condition, based on the extracted identifiers, andcomparing the searched condition with the data to determine whether thecondition is satisfied, and generating an event, when the condition issatisfied.
 12. The processing method of data according to claim 10,further comprising: providing a first action table that stores inadvance processing performed when the condition is satisfied,correspondingly to the identifiers, and performing processing stored inthe first action table, based on the identifiers, when the eventgenerator generates an event.
 13. The processing method of dataaccording to claim 10, further comprising: processing the data whenprocessing stored in the first action table is processing that processesdata transmitted from the sensor nodes, and adding an identifier to theprocessed data.
 14. The processing method of data according to claim 12,further comprising: receiving a model name from a user terminal, andsemantic information indicating a state of the model name; selecting aninformation storage destination and data to be monitored by refering tothe model list based on the model name; deciding a condition of data tobe monitored by referring to the semantic interpretation list based onthe semantic information; sending the selected monitoring object and thedecided condition to the information storage destination, notifying theprocessing to be executed, based on a request from the user terminal,and setting the processing to be executed in the first action tablebased on the notification.
 15. The processing method of data accordingto claim 11, further comprising: providing a first action table in whichfile names of files describing processing to be executed are specifiedcorrespondingly to the identifiers; providing a second action table thatstores the files describing the processing to be executed, and executingprocessing of files stored in the second action table, based on filenames stored in the first action table based on the identifiers.
 16. Theprocessing method of data according to claim 15, further comprising:comparing the condition with the data in place of the event conditionparser to determine whether the condition is satisfied, when executing afile stored in the second action table; and deciding processing to beexecuted when the condition is satisfied.